High-frequency circuit which can be switched on the basis of a temperature, and method for calibrating an analysis unit

Abstract

The invention relates to a high-frequency circuit which can be switched on the basis of a temperature for use when calibrating an analysis unit for high-frequency signals, said high frequency circuit having an input, a first standard, a second standard, a third standard, a first superconductor with a first transition temperature, a second superconductor with a second transition temperature and a third superconductor with a third transition temperature. Furthermore, the transition temperatures are different from each other, and above the transition temperatures, the first standard is electrically connected to the input such that a property of the first standard can be measured. Furthermore, the second standard is electrically connected to the input when the temperature falls below a first transition temperature so that a property of the second standard can be measured, the third standard is electrically connected to the input when the temperature falls below a second transition temperature so that a property of the third standard can be measured, and when a third transition temperature is undershot, a connection for a test object is electrically connected to the input so that a property of the test object can be measured.

Description

[0001] Temperature-dependent switchable high-frequency circuit and a method for calibrating an analysis unit

[0002] The present invention relates to a temperature-dependent switchable high-frequency circuit and a method for calibrating an analysis unit.

[0003] In electrical measurement technology, as well as radio-frequency and microwave technology, the measurement of unknown electrical properties of test objects or electrical assemblies is an important task. Electrical assemblies often use at least one port, a combination of an electrical input and output. If an electrical assemblies have multiple ports, they are referred to as two-port and multi-port measurements.

[0004] Scattering parameters are often measured to characterize electrical arrangements or test objects. Scattering parameters include reflection factors, transmission factors, and a reference impedance. Specifically, a signal sent into the electrical arrangement or test object is compared with the reflected or transmitted signal, and the scattering parameters, for example, are determined from this.

[0005] In addition, high-frequency technology usually measures the frequency dependence of the scattering parameters over a finitely wide frequency band. This is referred to as network analysis. A network analyzer usually has a test signal source and one or more receivers to record the signal response to the test signal. The scattering parameters of the electrical arrangement or test object are determined from the signal response(s) to one or more test signals. If the phase information of the scattering parameters is recorded, this is a vector network analysis. If only the absolute value is recorded, the network analysis is scalar. Current network analyzers offer various options for the measurement method, the number of ports, and the measurement frequency range.

[0006] In electrical circuits, components with unknown and non-ideal properties, such as cables, lead to systematic measurement errors. Therefore, calibration measurements are required to determine the circuit's unknown electrical parameters. Calibration standards are typically used for calibration. Calibration serves to correct the measurement results for systematic measurement errors. This allows for correction of the final results, so that the behavior of the test object can be determined without undesirable influences such as frequency-dependent attenuation from, for example, supply lines or other elements of the test setup.

[0007] In a one-port measurement, i.e. the measurement of the electrical parameters of a circuit with one port, three unknown parameters must be determined from which the unknown electrical property of a test object can then be calculated.

[0008] US20210218367A1 describes a superconducting capacitor consisting of three mutually isolated superconducting regions. These serve to tune the resonant frequency of a superconducting resonator.

[0009] US11557708B2 describes several Josephson junctions connected in series as a voltage standard. However, the Josephson junctions are each implemented in a separate standard.

[0010] In research, a wide variety of experiments, for example, for quantum standards and qubits, are conducted at low temperatures within cryostats. The required high-frequency lines are routed over a very wide temperature range with a corresponding gradient from the input to the test object. Currently, these RF systems are complex to calibrate at different temperatures using standards or to correct measurement errors. The respective standard is measured in a separate installed state to determine the calibration state of the entire system. Further measurements follow with other standards, each of which requires a further cooling process. The operational effort involved is high and time-consuming.

[0011] Therefore, it is an object of the present invention to provide an improved high-frequency circuit and an improved method for calibrating an analysis unit.

[0012] The problem is solved by the independent claims. Dependent claims specify advantageous further developments. The given examples can be combined with the independent claims and further developments.

[0013] A first aspect relates to a temperature-dependent switchable high-frequency circuit for use in calibrating an analysis unit for high-frequency signals, wherein the high-frequency circuit has an input, a first standard, a second standard, a third standard, a first superconductor with a first transition temperature, a second superconductor with a second transition temperature, and a third superconductor with a third transition temperature. Furthermore, it is provided that the transition temperatures are different from one another, wherein above the transition temperatures, the first standard is electrically connected to the input, so that a property of the first standard is measurable.It is further provided that when a first transition temperature is undershot, the second standard is electrically connected to the input so that a property of the second standard can be measured, and when a second transition temperature is undershot, the third standard is electrically connected to the input so that a property of the third standard can be measured, and when a third transition temperature is undershot, a connection for a test object is electrically connected to the input so that a property of the test object can be measured.

[0014] In other words, a high-frequency circuit is disclosed in which, depending on a temperature of the high-frequency circuit, the first, second and / or third superconductor becomes electrically conductive when the temperature falls below the respective transition temperature. The respective superconductor can be insulating or highly resistive above the corresponding transition temperature. When the temperature falls below the transition temperature, the superconductor can transition into a superconducting state. In particular, it can be provided that the superconductor is already superconducting upon reaching its respective transition temperature. In particular, it is provided that the superconductor is insulating or highly resistive above the respective transition temperature and only becomes superconducting when the temperature falls below the respective transition temperature. Furthermore, it is provided that the superconductor is also superconducting below its transition temperature.

[0015] By changing the state from high-resistance or insulating to superconducting, the superconductor can be used as a switch so that components, in particular the corresponding standards, can be switched on depending on the temperature, in particular they can be electrically connected to the input.

[0016] This has the advantage that the high-frequency circuit can be arranged in a container separated from the environment, in particular from environmental influences. A cryostat can be provided as the container, so that the high-frequency circuit can be cooled to a temperature above the first transition temperature or below the respective transition temperatures.

[0017] In particular, the standards can be arranged in such a way that each of the standards can be connected to the input individually or independently. In this case, one superconductor would be arranged in front of the respective standard with respect to the input, and one superconductor and one standard would be arranged parallel to each other.

[0018] It can also be provided that the standards and superconductors are arranged alternately in a series circuit, starting with the first standard from the input.

[0019] Different combinations of the previously described parallel arrangement and the series connection are also conceivable.

[0020] This has the advantage that each individual standard can be measured at a predefined temperature or with a predefined temperature profile. In the case of a series connection, a single standard can be measured first, and when the corresponding transition temperature is exceeded, the first standard and the second standard can be measured by connecting another standard.

[0021] Based on the measurement of the standard, an analysis unit can be calibrated so that a test object connected to the connector can be measured taking the calibration into account. This allows for particularly precise measurements. In particular, it is intended that three standards be used for the measurement. It can also be intended that at least three standards, in particular four, five, or six standards, be used.

[0022] One of the advantages is that by combining the three superconductors with the described temperature properties and the described electrical connection, measurements can be taken at three different temperatures, thus determining three unknown parameters of the high-frequency circuit. From the three determined parameters, it is possible to calculate the behavior of the high-frequency circuit according to a one-port measurement. Another advantage is that, unlike conventional measuring devices, no control lines are required, which reduces heat input. Furthermore, no assembly is required between measurements, as the electrical properties of the high-frequency circuit and the connectable test object can be measured without intermediate warm-up of the high-frequency circuit. A cooling unit can be arranged externally to the high-frequency circuit.In addition, due to their special electrical properties, superconductors are suitable for particularly precise determination of the electrical behavior of the high-frequency circuit, allowing the systematic measurement errors caused by the high-frequency circuit to be determined with particular precision. This allows test objects, when electrically connected to the high-frequency circuit, to be electrically measured with particular precision.

[0023] A further advantage is that with the high-frequency circuit, such a measurement is possible without repeated cooling, reheating, and re-cooling of the high-frequency circuit, since the superconductors do not have to be installed and / or removed during the measurement. Instead, for example, during a single continuous or step-by-step cooling process of the high-frequency circuit, one of the three unknown parameters of the arrangement can be measured whenever one of the transition temperatures is exceeded, since a standard is connected to the input whenever one of the transition temperatures is exceeded.

[0024] The described connection of the superconductors is advantageous for this purpose: at a temperature above the first transition temperature, the first standard is electrically connected to the input, at a temperature below the first transition temperature, the second standard is electrically connected to the input, and below the second transition temperature, the third standard is electrically connected to the input. Furthermore, the connection for the test object is electrically connected to the input at a temperature below the third transition temperature. Below its transition temperature, the superconductor has zero electrical resistance. This allows the offset length of the high-frequency circuit to change whenever the temperature falls below one of the transition temperatures. The offset length is understood to be the length from the input of the arrangement to the electrically insulating element of the arrangement that is electrically closest to the input.An electromagnetic wave applied at the input is reflected by this first insulating element. For example, the offset length of a series circuit consisting of three elements E1, E2, E3, where E1 is at the input, E3 is at the output, and E2 is between E1 and E3, is the length from the input through E1 up to and including E2 if only E3 is electrically insulating, while E1 and E2 are electrically conductive. In contrast, the offset length would only be up to and including E1 if E2 is insulating. The latter case would be unchanged if E2 were insulating but E1 and E3 were conductive.

[0025] In the context of this application, two or more electrically connected elements are understood in particular to mean that there is a connection between the elements, which either comprises direct physical contact between two adjacent elements or a mechanical connection between two adjacent elements by means of an electrically conductive component, for example an electrical line. In the context of this description, "connected" is understood in particular to mean electrically connected, for example electrically conductively connected, wherein the connection is preferably low-loss, i.e., it has low insertion loss. For example, the connection is direct, i.e., mechanical, or indirect via electrically conductive materials, for example, electrical cables.

[0026] The electrical input is particularly suitable for applying an external electromagnetic wave, so that the electromagnetic wave is conducted through at least part of the electrical high-frequency circuit. The electrical output is particularly suitable for measuring the electromagnetic wave that is propagated through at least part of the electrical high-frequency circuit.

[0027] The arrangement may have multiple inputs and / or outputs. The arrangement may include additional superconductors and / or additional elements, such as electrical wires, resistors, or the like.

[0028] A superconductor is understood to be an element made of a material that transitions into the superconducting state below a certain transition temperature. The superconductors in the inventive high-frequency circuit are preferably those that are electrical insulators above the transition temperature. Furthermore, a superconductor can be, for example, a switch based on a superconductor.

[0029] The electrical property being measured is, in particular, the impedance and / or at least one scattering parameter. Scattering parameters include, for example, an input reflection factor, an output reflection factor, a forward transmission factor, and / or a reverse transmission factor. These factors are measured, for example, as the amplification or attenuation experienced by an electromagnetic signal or electromagnetic wave applied to the input. The signal is applied and / or the measurement is performed, for example, using an analysis unit. In one embodiment, it can be provided that, when the temperature falls below the first transition temperature and exceeds the second transition temperature, only the second standard is electrically connected to the input.

[0030] In other words, it is provided that only the second standard is connected to the input. This should only be understood to mean that neither the first standard nor the third standard and / or the connection for the test object is electrically connected to the input. In this embodiment, it can be provided that the first superconductor, the second superconductor and the third superconductor are designed as changeover switches. In particular, it can be provided that, with regard to the input, the second superconductor is connected in series to the first superconductor and the second superconductor to the third superconductor. Consequently, by falling below the first transition temperature and above the third transition temperature, the second standard can be electrically connected to the input by means of the first superconductor and the second superconductor.In particular, it can be provided that the first standard, the second standard, the third standard and the connection for the test object are arranged parallel to one another.

[0031] This has the advantage that the second standard can be measured without interference with the first standard, the third standard, and / or the connection for the test object. This enables particularly precise measurements.

[0032] In this case, particular use is made of the property that the superconductors are designed as switches, so that one of the superconductors, for example the second superconductor, is connected to the input and, depending on the temperature above the second transition temperature, to the first superconductor and, below the second transition temperature, to the third superconductor, wherein the first superconductor is connected to the first standard depending on the temperature above the first transition temperature and to the second standard below the first transition temperature, and wherein the third superconductor is connected to the third standard above the third transition temperature and, below the third transition temperature, to the connection for the test object.In a further embodiment, it can be provided that when the temperature falls below the second transition temperature and is above the third transition temperature, only the third standard is electrically connected to the input.

[0033] In other words, it is provided that only the third standard is connected to the input. This should only be understood to mean that neither the first standard nor the second standard and / or the connection for the test object is electrically connected to the input. In this embodiment, it can be provided that the first superconductor, the second superconductor and the third superconductor are designed as changeover switches. In particular, it can be provided that, with regard to the input, the second superconductor is connected in series to the first superconductor and the second superconductor is connected in series to the third superconductor. Consequently, by falling below the second transition temperature and above the third transition temperature, the third standard can be electrically connected to the input by means of the second superconductor and the third superconductor.When the temperature of the second superconductor falls below the second transition temperature, the first superconductor is no longer electrically connected to the input.

[0034] This has the advantage that the third standard can be measured without interference with the first standard, the second standard, and / or the connection for the test object. This enables particularly precise measurements.

[0035] In a further embodiment, it can be provided that when the third transition temperature is undershot, only the connection for the test object is electrically connected to the input.

[0036] In other words, it is provided that only the connection for the test object is connected to the input. This should only be understood to mean that neither the first standard, the second standard, nor the third standard is electrically connected to the input. In this embodiment, it can be provided that the first superconductor, the second superconductor, and the third superconductor are designed as changeover switches. In particular, it can be provided that, with regard to the input, the second superconductor is connected in series to the first superconductor and the second superconductor is connected in series to the third superconductor. Consequently, by falling below the third critical temperature, the connection of the test object can be electrically connected to the input by means of the second superconductor and the third superconductor.When the temperature of the third superconductor falls below the third transition temperature, the first superconductor is no longer electrically connected to the input and the third superconductor switches between the third standard and the connection for the test object.

[0037] This has the advantage that the test object, which can be connected to the high-frequency circuit via the test object connector, can be measured without interference with the first standard, the second standard, and / or the third standard. This enables particularly precise measurements.

[0038] In a further embodiment, it can be provided that at least one of the superconductors (41, 42, 32) is designed as a changeover switch, so that depending on a temperature of the high-frequency circuit 20 and the corresponding transition temperature T41, T42, T43 of the at least one superconductor 41, 42, 43, only a single standard (N1, N2, N3) or test object DUT is electrically connected to the input.

[0039] It can be provided that at least one of the superconductors has a superconductor input and a first output and a second output. Depending on the temperature, either the first output or the second output can be connected to the superconductor input by falling below the critical temperature of the corresponding superconductor. This allows, for example, if a first standard is connected to the first output and a second standard is connected to the second output, either the first standard or the second standard can be connected to the input of the high-frequency circuit.

[0040] In a further embodiment, the first superconductor, the second superconductor, and the third superconductor can be configured as changeover switches. This has the advantage that, by falling below one of the critical temperatures, different configurations with respect to the standard and the connection for the test object can be connected to the input. In particular, by falling below one of the critical temperatures, one or more standards and / or the connection for the test object can be electrically separated from the input.

[0041] It can also be provided that by falling below the first transition temperature T41 and above the second transition temperature T42, the first standard N1 and the second standard N2 are electrically connected to the input 30

[0042] It can also be provided that by falling below the second transition temperature T42 and above the third transition temperature T43, the first standard N1, the second standard N2 and the third standard N3 are electrically connected to the input 30.

[0043] In one embodiment, it can be provided that when the third transition temperature is undershot, the first standard, the second standard, the third standard and the connection for the test object are electrically connected to the input.

[0044] The three superconductors can be in direct physical contact with one another or electrically connected to one another by means of electrical conductors. The first superconductor is directly or electrically connected to the second superconductor, and the second superconductor is directly or electrically connected to the third superconductor. In particular, it can be provided that the first standard is arranged in front of the first superconductor and the connection for the test object is arranged behind the third superconductor with respect to the input. Furthermore, it can be provided that the second standard is arranged between the first superconductor and the second superconductor, and the third standard is arranged between the second superconductor and the third superconductor. The first superconductor can be connected to the input. If the high-frequency circuit has three superconductors, the third superconductor is connected to the connection for the test object.

[0045] Optionally, the arrangement can have more than three superconductors. In this case, the rearmost superconductor with respect to the input is connected to the connection for the test object. This allows measurement of three unknown parameters of the high-frequency circuit at three measurement temperatures: the first temperature is above the first transition temperature, the second measurement temperature is between the first and second transition temperatures, and the third measurement temperature is between the second and third transition temperatures. Thus, when an electromagnetic wave is applied to the input of the high-frequency circuit at the first measurement temperature, the offset length is exclusive to the first superconductor, since this is in an insulating state, with the second and third superconductors also insulating.At the second measurement temperature, the offset length is exclusive of the second superconductor, since the first superconductor is in the superconducting state, while the second and third superconductors are insulating. At the third measurement temperature, the offset length is exclusive of the third superconductor, so the electromagnetic wave applied at the input can propagate to the third superconductor.

[0046] Thus, a single measurement at each of the three measurement temperatures allows for the determination of the three unknown parameters of a one-port measurement. This allows a complete description of the behavior of the high-frequency circuit. Thus, the analysis unit can be calibrated using the high-frequency circuit, and the analysis unit can be used to measure test objects with unknown electrical properties while correcting systematic measurement errors. Such a calibrated analysis unit enables particularly precise measurement of the test object.

[0047] A particular advantage is that the three or four offset lengths are automatically generated by falling below the transition temperatures, without requiring any mechanical modification of the high-frequency circuit or switching. This eliminates the need for control cables, whose heat input would be detrimental.

[0048] In one embodiment, it can be provided that the first standard, second standard and third standard are each different from one another at least with regard to one electrical property. This has the advantage that the standards can have different properties below the different transition temperatures, so that calibration can be carried out as a function of the temperature.

[0049] A further aspect relates to a method for calibrating an analysis unit for measuring at least one electrical property of a test object by means of a temperature-dependent switchable high-frequency circuit according to one of the previous embodiments, comprising the steps: a) measuring a first electrical property of the first standard above the first transition temperature; b) measuring a second property of the second standard below the first transition temperature and above the second transition temperature; c) measuring a third electrical property of the third standard below the second transition temperature and above the third transition temperature; d) calibrating the analysis unit based on at least the first, second and third electrical properties; e) measuring the at least one electrical property of the test object by means of the calibrated analysis unit below the third transition temperature.

[0050] In other words, the high-frequency circuit is intended to be used to measure the electrical properties of standards at different temperatures. The method has the particular advantage that cooling can be carried out continuously or at least without intermediate heating and / or external influences. As an alternative to continuous cooling, it can also be provided that cooling is first carried out to the third transition temperature and, finally, that the standards are electrically isolated from the input upon exceeding the respective transition temperatures.

[0051] Preferably, however, the high-frequency circuit performs a measurement of a first electrical property of the standard above the first transition temperature. In this case, cooling to a temperature above the first transition temperature may already have occurred. In particular, the temperature may be below room temperature.

[0052] Furthermore, it can be provided that the measurement of the second property takes place when or after the first transition temperature is undershot, so that only the first superconductor is in a superconducting state.

[0053] Furthermore, the third electrical property can be measured at or after the temperature falls below the second transition temperature, so that at least the second superconductor is in a superconducting state. Preferably, the third superconductor is in an insulating state.

[0054] Furthermore, the fourth electrical property can be measured at or after the temperature falls below the third critical temperature, so that at least the third superconductor is in a superconducting state. Preferably, the first, second, and third superconductors are in a superconducting state. This enables the measurement of a test object that can be connected to the test object terminal.

[0055] Thus, the method enables either the respective measurement of only the first standard, second standard, third standard or the test object or alternatively the respective measurement of the first standard or the first standard and the second standard or the first standard, the second standard and the third standard or the first standard, the second standard, the third standard and the test object connectable to the connection for the test object.

[0056] In one embodiment, it can be provided that the respective measurement comprises the following steps: i) applying an alternating current signal, preferably with a frequency above 10 kHz, to the input and ii) during and / or after the application: detecting a signal response of the

[0057] High-frequency circuit to the applied alternating current signal at the input, iii) wherein the application occurs before, during and / or after falling below one of the transition temperatures.

[0058] The exemplary embodiments explained below represent a preferred embodiment of the invention. In the exemplary embodiment, the described components of the embodiment each represent individual, independently considered features of the invention, which also further develop the invention independently of one another and are thus also to be considered as components of the invention, either individually or in a combination other than that shown. Furthermore, the described embodiment can also be supplemented by further features of the invention already described.

[0059] In the figures, identical reference numerals designate functionally identical elements. Fig. 1 shows a device for measuring at least one electrical property of an electrical arrangement with a cooling unit and an analysis unit.

[0060] Fig. 2 shows an electrical arrangement of three superconductors connected in series with one input and one output.

[0061] Fig. 3 shows an electrical arrangement of three different superconductors used for switching.

[0062] Fig. 4 shows two electrical arrangements with three superconductors each.

[0063] Fig. 5 shows two electrical arrangements with seven superconductors each.

[0064] Fig. 6 shows a method for calibrating a device for measuring at least one electrical property of an electrical device.

[0065] Fig. 7 shows a method for calibrating a device for measuring at least one electrical property of an electrical device, wherein the measuring comprises applying an alternating current signal and detecting a signal response;

[0066] Fig. 8 shows a high-frequency circuit, wherein the normals are arranged one behind the other with respect to an input; and

[0067] Fig. 9 shows a high-frequency circuit, with the normals arranged side by side with respect to an input.

[0068] Fig. 1 shows a device 10 for measuring at least one electrical property of an electrical arrangement 20 with a cooling unit 60 and an analysis unit 50. The electrical arrangement 20 comprises an electrical input 30 and an electrical output 32 as well as at least three superconductors 41, 42, 43. The arrangement 20 is preferably realized as in one of Figures 2 to 4. The arrangement 20 is preferably positioned within the cooling unit 60. Preferably, the first superconductor 41 has a first transition temperature T41, the second superconductor 42 has a second transition temperature T42 and the third superconductor 43 has a third transition temperature T43. Preferably, the second transition temperature T42 is lower than the first transition temperature T41 and higher than the third transition temperature T43.Preferably, the arrangement 20 is suitable for the first standard N1 to be electrically connected to the input 30 at a temperature T above the first transition temperature T41; for the first superconductor 41 to be electrically connected to the input 30 at a temperature T between the first and second transition temperatures T41, T42, so that the first standard N1 and the second standard N2 are electrically connected to the input; and for the first to third superconductors 41-43 to be electrically connected to the input 30 at a temperature T between the second and third transition temperatures T42, T43, so that the first standard N1, the second standard N2 and the third standard N3 are electrically connected to the input.

[0069] Preferably, the analysis unit 50 is configured to detect at least one electrical property of the arrangement 20. The electrical property of the arrangement 20 is, for example, one or more scattering parameters such as input or output reflection factor or forward or reverse transmission factor. Preferably, the analysis unit 50 is further configured to apply an alternating current signal AC to the arrangement 20 and detect the signal response A. The arrangement 20 comprises, for example, a test object that is preferably integrated such that the test object is electrically connected to the input 30 only at a temperature T below the third transition temperature T43.

[0070] Fig. 2 shows an electrical arrangement 20 comprising three series-connected superconductors 41, 42, 43 with an input 30 and an output 32. The arrangement 20 comprises a first superconductor 41, a second superconductor 42, and a third superconductor 43, which are electrically connected to one another. The first superconductor 41 has a first transition temperature T41, the second superconductor 42 has a second transition temperature T42, and the third superconductor 43 has a third transition temperature T43. Preferably, the second transition temperature T42 is lower than the first transition temperature T41 and higher than the third transition temperature T43: T41 > T42 > T43.

[0071] The first superconductor 41 is electrically or directly physically connected to the input 30 and the second superconductor 42. The second superconductor 42 is electrically or directly physically connected to the first and third superconductors 41, 43. The third superconductor 43 is electrically or directly physically connected to the output 32 and the second superconductor 42. As a result, at a temperature T above the first transition temperature T41, the input 30 is electrically connected to the first superconductor 41. At a temperature between the second and the first transition temperature T42 <T<T41 ist der Eingang 30 elektrisch mit dem ersten und zweiten Supraleiter 41 , 42 verbunden. Bei einer Temperatur zwischen der dritten und der zweiten Sprungtemperatur T43<T<T42 ist der Eingang 30 elektrisch mit dem ersten bis dritten Supraleiter 41 , 42, 43 verbunden.At a temperature below the third transition temperature T <T43 ist der Eingang 30 elektrisch mit dem ersten, zweiten und dritten Supraleiter 41 , 42, 43 und mit dem Ausgang 32 verbunden. Somit ergeben sich vier unterschiedliche Versatzlängen L1 , L2, L3, L4 bei den vier beschriebenen Temperaturbereichen. Die Anordnung stellt somit beispielsweise drei verschiedene Normale N1 , N2, N3 bei den ersten drei beschriebenen Temperaturbereichen bereit. Beispielsweise kann ein Prüfobjekt DUT zwischen dem dritten Supraleiter 43 und dem Ausgang 32 integriert sein. Dadurch ist bei einer Temperatur unterhalb der dritten Sprungtemperatur T<T43 das Prüfobjekt DUT elektrisch mit dem Eingang 30 verbunden. Dadurch kann eine angeschlossene Analyseeinheit 50 die mindestens eine elektrische Eigenschaft des Prüfobjekts DUT messen.

[0072] Fig. 3 shows an electrical arrangement 20 comprising three superconductors 41, 42, 43, in which switching takes place between the first and third superconductors 41, 43 by means of the second superconductor 42. The transition temperatures T41, T42, T43 of the three superconductors 41, 42, 43 are preferably as described above for Fig. 2. Preferably, at a temperature T above the second transition temperature T42, the input 30 of the arrangement 20 is connected to the first superconductor 41. Preferably, at a temperature T below the second transition temperature T42, the input 30 of the arrangement 20 is connected to the third superconductor 43.Preferably, the switching between these connections is carried out automatically due to the temperature falling below the transition temperature, for example by means of interrupted or short-circuited lines of a length of a quarter wavelength of the resonant frequency of the alternating current signal AC emitted by the analysis unit 50.

[0073] Fig. 4 shows two electrical arrangements 20, 22, each with three superconductors, in which switching between the first and third superconductors 41, 43 is carried out by means of the second superconductor 42, and switching between the fourth and sixth superconductors 44, 46 is carried out by means of the fifth superconductor. The previous explanations for Fig. 4 apply to the first arrangement 20 with the first gate 33. The second arrangement 22 preferably has a second gate 34. The second arrangement 22 preferably has a fourth, fifth, and sixth superconductors 44, 45, 46, which are electrically connected to one another. The fourth superconductor 44 has a fourth transition temperature T44, the fifth superconductor 45 has a fifth transition temperature T45 and the sixth superconductor 46 has a sixth transition temperature T46, wherein preferably the fifth transition temperature T45 is lower than the fourth transition temperature T44 and higher than the sixth transition temperature T46: T44>T45>T46.

[0074] The analysis unit 50 is preferably configured for two-port and / or multi-port measurements. Preferably, the first and fourth transition temperatures are equal to T41 = T44, the second and fifth transition temperatures are equal to T42 = T45, and the third and sixth transition temperatures are equal to T43 = T46. Preferably, the two arrangements 20, 22 are arranged in a cooling unit 60.

[0075] Preferably, at a temperature above the first transition temperature, the first gate 33 is connected to a first known calibration standard N1, at a temperature between the first and second transition temperatures T41 <T<T42 mit einem zweiten bekannten Kalibriernormal N2 verbunden und bei einer Temperatur zwischen der zweiten und dritten Sprungtemperatur T42<T<T43 mit einem dritten bekannten Kalibriernormal N3 verbunden.

[0076] Preferably, the two assemblies 20, 22 are electrically connected to an analysis unit 50, which is preferably configured to detect the at least one electrical property of the assemblies 20, 22. For example, a test object (DUT) is connected to the assemblies 20, 22.

[0077] The test object is preferably electrically connected to the first gate 33 at a temperature below the third transition temperature T43.

[0078] Fig. 5 shows two electrical arrangements 20, 22, each with seven superconductors for two-port measurement with a test object (DUT). The seven superconductors of the first arrangement 20 have seven different transition temperatures. The seven superconductors of the second arrangement preferably have the same seven transition temperatures as the seven superconductors of the first arrangement. The seven superconductors of the first and second arrangements 20, 22 are preferably arranged such that the fourth superconductor of the first arrangement 20 is connected to the first port 33 and the fourth superconductor of the second arrangement 22 is connected to the second port 34. The first transition temperature is higher than the second, and so on, up to the seventh transition temperature, which is the lowest.The critical temperatures are preferably successively exceeded when measuring at least one electrical property of the test object from the first to the seventh, and one measurement is performed in each case, so that seven measurements of the seven standards (N1 to N7) are performed consecutively, as well as one measurement of the test object. It is possible to replace the fourth to seventh standards (N4 to N7) with one to four additional test objects.

[0079] The advantages of such an arrangement are that it improves calibration due to the overdetermination of the system of equations. Furthermore, it allows for the flexible calibration of a varying number of test objects within one electrical arrangement and within one cooling process. This eliminates the need for multiple insertion and removal of test objects and for repeated heating and cooling.

[0080] Fig. 6 shows a method 12 for calibrating a device 10 for measuring at least one electrical property of an electrical arrangement 20. The electrical arrangement 20 can be designed like one of the arrangements in Figs. 2 to 3, comprise two arrangements 20, 22 and two gates 33, 34 as in Fig. 4, for example, or comprise multiple gates as in Fig. 5, for example. The method 12 comprises at least a first, second, and third cooling 71, 72, 73 to three measuring temperatures. Furthermore, the method 12 comprises measuring 81, 82, 83 the at least one electrical property of the arrangement 20 at three different measuring temperatures. Preferably, the first measuring temperature is above the first transition temperature T>T41, the second measuring temperature is between the first and second transition temperatures T41. <T<T42, die dritte Messtemperatur zwischen der zweiten und der dritten Sprungtemperatur T42<T<T43 und die vierte Messtemperatur unterhalb der dritten Sprungtemperatur T<T43.The measurements 81, 82, 83, 84 can take place during and / or after the respective superconductor 41, 42, 43 has switched to the superconducting state. Cooling is implemented, for example, using a cooling unit 60. The measurements are preferably taken using an analysis unit 50. The arrangement 20 can have a test object DUT. In this case, a fourth measurement 84 of the at least one electrical property of the test object DUT is preferably also carried out. The electrical property refers to the abstract measured parameter. The electrical property is, for example, one or more of the scattering parameters. Preferably, the same parameter(s) are measured in each of the four measurements. The specific measured value is generally different for each of the individual measurements. A calibration value or an error correction of the arrangement 20 or the test object DUT is calculated from the individual measured values, preferably after the last measurement.

[0081] Fig. 7 shows a method 12 for calibrating a device 10 for measuring at least one electrical property of an electrical arrangement 20, wherein the measuring 81, 82, 83, 84 each comprise the application 100a-d of an alternating current signal AC and the detection 110a-d of a signal response A. The application 100a-d and detection 110a-d are preferably performed by the analysis unit 50. The analysis unit 50 preferably determines the at least one electrical property of the arrangement 20 from the alternating current signal AC, which serves as a test signal, and the detected signal response A.

[0082] The arrangement 20 can comprise a test object DUT. In this case, a fourth measurement 84 of the at least one electrical property of the test object DUT from the test signal and the detected signal response A is preferably additionally performed by the analysis unit 50, preferably at a temperature below the lowest critical temperature of the superconductors arranged in the arrangement.

[0083] Figure 8 shows a high-frequency circuit 20, wherein the standards N1, N2, N3 are arranged in series with one another. The high-frequency circuit 20 has an input 30. The input 30 is electrically connected to a first standard N1. Furthermore, the first standard N1 is connected in series with a first superconductor 41. In this case, the first superconductor is electrically connected to a second standard N2 as a function of a temperature T by falling below a transition temperature T41 of the first superconductor, so that the second standard N2 is also electrically connected to the input 30. Consequently, when the first transition temperature is fallen below, the first standard N1 and the second standard N2 are electrically connected to the input 30. Furthermore, the high-frequency circuit 20 has a second superconductor 42, which is connected to the third standard N3, so that when the second transition temperature T42 is fallen below, the third standard N3 is additionally electrically connected to the input 30.Thus, above the first transition temperature T41, only the first standard N1 is connected to the input 30. Above the second transition temperature T42, below the first transition temperature T41, and above a third transition temperature T43, only the first standard N1 and the second standard N2 are electrically connected to the input 30. Above the third transition temperature T43 and below the second transition temperature T42, only the first standard N1, the second standard N2, and the third standard N3 are electrically connected to the input 30. When the temperature falls below the third transition temperature T43, in addition to the first standard N1, second standard N2, and third standard N3, the connection for the test object 31 is also connected to the input.

[0084] Figure 9 shows a high-frequency circuit 20, wherein the standards N1, N2, N3 are arranged in parallel. The high-frequency circuit 20 has an input 30. The input 30 is connected to a second superconductor 42. In particular, the second superconductor 42 has a superconductor input and a first superconductor output, and a second superconductor output, wherein the first superconductor output is electrically connected to a first superconductor 41 and the second output is electrically connected to a third superconductor 43. The superconductor input is electrically connected to the input 30.

[0085] Furthermore, the first superconductor 41 likewise has two outputs and one input, wherein the input of the first superconductor 41 is electrically connected to the first output of the second superconductor 42. Furthermore, the third superconductor likewise has one input and two outputs, wherein the input of the third superconductor 43 is electrically connected to the second output of the second superconductor 42, so that, depending on the temperature T of the high-frequency circuit 20, when a second transition temperature of the second superconductor T42 is undershot or exceeded, either the first superconductor 41 or the third superconductor 43 is electrically connected to the input 30. A first output of the first superconductor is electrically connected to a first standard N1, so that above the first transition temperature T41 and above the second transition temperature, the first standard N1 is electrically connected to the input 30.In particular, only the first standard N1 is electrically connected to the input 30.

[0086] Furthermore, the second output of the first superconductor 41 is connected to a second standard N2, so that when the temperature falls below the first transition temperature T41 and exceeds the second transition temperature T42, the second standard N2 is electrically connected to the input. In particular, only the second standard N2 is electrically connected to the input 30.

[0087] The third superconductor 43 also has an input and a first and second output. The input of the third superconductor 43 is electrically connected to the second output of the second superconductor. The first output of the third superconductor is electrically connected to a third standard N3, so that the third standard N3 is electrically connected to the input when the temperature falls below the second transition temperature T42 and exceeds the third transition temperature T43. In particular, only the third standard N3 is electrically connected to the input 30.

[0088] Furthermore, a terminal for a test object 31 is electrically connected to the second output of the third superconductor 43, so that when the temperature falls below the third transition temperature T43, the terminal for the test object 31 is electrically connected to the input. In particular, only the terminal for the test object 31 is electrically connected to the input 30. The terminal for the test object 31 is designed to connect a test object DUT, so that below the third transition temperature T43, only the test object DUT is connected to the input 30.

[0089] A first example relates to a device 10 for measuring at least one electrical property of an electrical arrangement 20, wherein the arrangement 20 has an electrical input 30 and an electrical output 32, the arrangement 20 has a first superconductor 41, a second superconductor 42 and a third superconductor 43 which are electrically connected to one another; the first superconductor 41 has a first transition temperature T41, the second superconductor 42 has a second transition temperature T42 and the third superconductor 43 has a third transition temperature T43; the second transition temperature T42 is lower than the first transition temperature T41 and higher than the third transition temperature T43; the arrangement 20 is suitable such that at a temperature T above the first transition temperature T41 the first superconductor is connected to the input 30;At a temperature T between the first transition temperature T41 and the second transition temperature T42, the first 41 and second superconductor 42 are connected to the input 30; At a temperature T between the second transition temperature T42 and the third transition temperature T43, the third superconductor 43 is connected to the input 30.

[0090] A second example relates to a device 10 according to the first example, wherein the at least three superconductors 41, 42, 43 are connected in series with one another, so that at a temperature T below the third transition temperature T43 the first, second and third superconductors 41, 42, 43 are connected to the input 30.

[0091] A third example relates to a device 10 according to one of the previous examples, wherein the second superconductor 42 is configured to switch from the first superconductor 41 to the third superconductor 43 when the temperature falls below the second transition temperature T42, and the arrangement 20 is suitable such that, at a temperature T above the second transition temperature T42, the input 30 of the arrangement 20 is connected to the first superconductor 41; and at a temperature T below the second transition temperature T42, the input 30 of the arrangement 20 is connected to the third superconductor 43.

[0092] A fourth example relates to a device 10 according to one of the previous examples, further comprising a cooling unit 60 which is configured to cool the arrangement 20 to a temperature T below the first, second, and / or third transition temperature T41, T42, T43.

[0093] A fifth example relates to a device 10 according to one of the previous examples, further comprising an analysis unit 50 configured to detect the at least one electrical property of the arrangement 20. The analysis unit 50 can, in particular, be configured to detect the at least one electrical property of the arrangement 20 at the three measurement temperatures T41, T42, T43 described above. Preferably, the at least one electrical property of the arrangement 20 comprises the impedance and / or at least one scattering parameter, as described above.

[0094] A sixth example relates to a device 10 according to example 5, wherein the analysis unit 50 is further configured to feed an alternating current AC, preferably with a frequency f above 10 kHz, into the arrangement 20 and to detect a signal response A of the arrangement 20.

[0095] In this case, the supplied alternating current serves as a test signal. The electrical property that the analysis unit 50 can be configured to detect comprises, for example, at least one property of the signal response, for example a frequency or a plurality of frequency components, a phase and / or an amplitude or a magnitude. From the detected property of the signal response, the analysis unit 50 can determine the electrical property of the arrangement 20, for example in the form of attenuation and / or amplification, a phase shift, or the like. Preferably, the supplied alternating current signal can have a plurality of frequencies and / or the analysis unit 50 can be configured to detect a plurality of alternating current signals with different frequencies, so that a frequency-dependent determination of the electrical property of the arrangement 20 is preferably carried out.For example, the frequency range within which the signal has components and / or within which several signals are fed in comprises frequencies between a minimum and a maximum.

[0096] This enables characterization of the electrical properties of the arrangement 20 in the high-frequency range. Consequently, measurements of frequency-dependent high-frequency properties of test objects are subsequently possible with the arrangement calibrated in this way. A seventh example relates to a device 10 according to one of examples 5 or 6, wherein the analysis unit 50 is configured to detect the at least one electrical property of the arrangement 20 before, during and / or after one of the superconductors 41, 42, 43 falls below the first, second and / or third transition temperature T41, T42, T43, and wherein the analysis unit 50 is preferably configured to detect a step response of the arrangement 20 during the transition of one of the superconductors 41, 42, 43 into the superconducting state.

[0097] An eighth example relates to a device 10 according to any one of examples 5 to 7, wherein the arrangement 20 further comprises a test object DUT that is electrically connected to the input 30 or output 32, and wherein the analysis unit 50 is configured to calculate at least one electrical property of the test object DUT from the at least one detected electrical property of the arrangement 20.

[0098] This enables the unknown electrical behavior of the test object (DUT) to be determined with high precision. Another advantage is that, unlike conventional measuring devices using superconductors, no control lines are required, which reduces heat input. Furthermore, no assembly is required between measurements, since the measurements of the electrical properties of the arrangement and the test object can be performed without intermediate heating of the arrangement 20. The arrangement 20 preferably has a cooling unit. The arrangement preferably has an analysis unit 50. The measurements of the electrical properties of the arrangement 20 and the test object (DUT) are preferably performed within a cooling process. At least one measurement is performed by the analysis unit 50 whenever the temperature falls below one of the critical temperatures T41, T42, T43 of the three superconductors 41, 42, 43.

[0099] For example, the test object DUT is integrated in the arrangement 20 such that it is electrically connected to one of the superconductors 41, 42, 43 and to the output 32 of the arrangement 20. In the case of a series connection of the superconductors 41, 42, 43, the test object DUT is preferably integrated between the third superconductor 43 and the output 32. When switching between the first 41 and third superconductor 43 by means of the second superconductor 42, the test object DUT is preferably integrated such that at a temperature ? below the third transition temperature T43, the input 30 is electrically connected to the test object DUT and the output 32.

[0100] Preferably, at a temperature T above the first transition temperature T41, the input 30 is connected to a first standard N1, at a temperature T between the first T41 and second transition temperature T42 it is connected to a second known standard N2, and at a temperature T below the second transition temperature T42 it is connected to a third known standard N3.

[0101] It is possible for the arrangement to comprise more than three superconductors. If the arrangement comprises N superconductors with N transition temperatures, the input 30 is preferably connected to an nth standard at a temperature T between the nth and (n-1)th transition temperature, where n is between 2 and N.

[0102] For example, the analysis unit 50 is configured to first detect at least one electrical property of the arrangement 20 at the three measurement temperatures described above and then to determine at least one electrical property of the test object DUT. This can be done, for example, by means of a calculation corresponding to a one-port measurement from three variables to be determined. For example, the input reflection factor, the output reflection factor, the forward transmission factor, and / or the reverse transmission factor are detected for each of the three measurement temperatures.

[0103] Preferably, the test object DUT is arranged such that it is electrically connected to the input 30 below the third transition temperature T43, in particular if the arrangement 20 comprises three superconductors 41, 42, 43.

[0104] Optionally, one or more of the following measurements are additionally performed by the evaluation unit 50: differential parameter and receiver measurement, limit value, residual ripple test, time domain parameter analysis, scattering parameters and / or frequency spectrum analysis.

[0105] A ninth example relates to a device 10 according to any one of examples 5 to 8, further comprising at least one second arrangement 22 which is electrically connected to the first arrangement 20, wherein the input and output of the first arrangement form a first gate 33 and the second arrangement 22 has a second gate 34, the second arrangement 22 has a fourth, fifth and sixth superconductor 44, 45, 46 which are electrically connected to one another; the fourth superconductor 44 has a fourth transition temperature T44, the fifth superconductor 45 has a fifth transition temperature T45 and the sixth superconductor 46 has a sixth transition temperature T46; the fifth transition temperature T45 is lower than the fourth transition temperature T44 and higher than the sixth transition temperature T46; and wherein the analysis unit 50 is designed for two-port and / or multi-port measurement.

[0106] This design with two electrical arrangements enables two-port measurements and the calibration of circuits with seven unknown parameters.

[0107] Preferably, the fourth transition temperature is the same as the first transition temperature T41. The same preferably applies to the second T42 and fifth, as well as to the third T43 and sixth transition temperatures.

[0108] For example, the three superconductors of the second arrangement are connected in series. Preferably, when the superconductors of the second arrangement are connected in series, the fourth superconductor is electrically connected to the input of the second arrangement, and the sixth superconductor is electrically connected to the output of the second arrangement. Alternatively, for example, the fifth superconductor is configured to switch between the fourth and sixth superconductors.

[0109] The second arrangement may be designed like the first arrangement 20, as explained in the above embodiments.

[0110] The device 10 can, for example, have a cooling unit 60 and / or an analysis unit 50, which is configured to cool or measure both arrangements.

[0111] The analysis unit 50 is preferably connected to the input 30 or output 32 of the arrangement 20.

[0112] The device 10 can have a test object DUT. The test object DUT can, for example, be integrated into the two arrangements as follows: The second superconductor 42 of the first arrangement 10 is, for example, connected to the input 30 of the first arrangement 10, which in this case represents a first gate. The fifth superconductor is preferably connected to the input of the second arrangement, which in this case represents a second gate. The second superconductor 42 is, for example, configured to switch between the first 41 and the third superconductor 43. Preferably, at a temperature T above the second transition temperature T42, the first gate is electrically connected to the first superconductor 41 and preferably the second gate is electrically connected to the fourth superconductor.Preferably, at a temperature T below the second transition temperature T42 but above the third transition temperature T43, the first gate is connected to the third superconductor 43 and the second gate is connected to the sixth superconductor. At a temperature T below the third transition temperature T43, the first gate and the second gate are preferably electrically connected to the third 43 and sixth superconductors, as well as to the test object DUT.

[0113] Preferably, the first transition temperature T41 corresponds to the fourth transition temperature.

[0114] Preferably, the second transition temperature T42 corresponds to the fifth transition temperature.

[0115] Preferably, the third transition temperature T43 corresponds to the sixth transition temperature.

[0116] As a result, the first 20 and second arrangement are preferably designed such that they are suitable for an electromagnetic wave applied to the input 30 of the first arrangement 20 to propagate through the first superconductor 41 at a temperature T above the first transition temperature T41, then to propagate through a first standard N1 arranged between the first superconductor 41 and the fourth superconductor and to arrive measurably at the input of the second arrangement.

[0117] Furthermore, the first 20 and second arrangement are preferably designed such that they are suitable for an electromagnetic wave applied to the input 30 of the first arrangement 20 to propagate through the first superconductor 41 at a temperature T between the first T41 and the second transition temperature T42, then to propagate through a second standard N2 arranged between the first superconductor 41 and the fourth superconductor and to arrive measurably at the input of the second arrangement.

[0118] Furthermore, the first 20 and second arrangement are preferably designed such that they are suitable for an electromagnetic wave applied to the input 30 of the first arrangement 20 to propagate through the third superconductor 43 of the first arrangement 20 at a temperature T between the second T42 and the third transition temperature T43, then to propagate through a third standard N3 arranged between the third superconductor 43 and the sixth superconductor and to arrive measurably at the input of the second arrangement.

[0119] The device 10 may have further arrangements so that a plurality of gates is obtained.

[0120] A tenth example relates to a method 12 for calibrating a device 10 for measuring at least one electrical property of an electrical arrangement 20 according to one of the preceding claims, comprising the steps: first measurement 81 of the at least one electrical property of the arrangement 20 at a temperature above the first critical temperature T41; first cooling 71 of the arrangement 20 below the first critical temperature T41, so that when the temperature falls below the first critical temperature T41, a first offset length L1 of the arrangement 20 results and serves as the first standard N1; after the first cooling 71: second measurement 81 of the at least one electrical property of the arrangement 20;after the second measurement 81: second cooling 72 of the arrangement 20 below the second transition temperature T42, so that due to the switching of the second superconductor 42 into the superconducting state, a second offset length L2 results and / or the electrical connection between the superconductors changes and serves as a second standard N2; after the second cooling 72: third measurement 82 of the at least one electrical property of the arrangement 20, after the third measurement 82: third cooling 73 of the arrangement 20 below the third transition temperature T43, so that due to the switching of the third superconductor 43 into the superconducting state, a third offset length L3 results and / or the electrical connection between the superconductors changes and serves as a second standard N3; after the third cooling 73: fourth measurement 83 of the at least one electrical property of the arrangement 20;and from the four measurements of the at least one electrical property: calculating 90 at least one further electrical property of the arrangement and / or a device under test (DUT) electrically connected to the arrangement 20;

[0121] N superconductors can be arranged in the array 20, and in this case, N standards can be used, and a measurement can be performed on a test object (DUT). One or more electrical properties can be measured. In this application, an electrical property does not refer to a concrete numerical measured value, but rather to an abstract parameter. For example, an electrical property is the reflection attenuation. A concrete measured value of this is, for example, 10 dB.

[0122] This enables temperature-dependent switching of the offset length without additional control lines or intermediate warm-up of the arrangement.

[0123] The three offset lengths L1, L2, and L3 allow the measurement of three standards N1, N2, and N3 for calibration. From these three measurements, three unknown parameters of the arrangement 20 can be determined. This allows a complete characterization corresponding to a one-port measurement.

[0124] The analysis unit 50 is preferably configured for single-port measurement. A test object (DUT) can preferably be integrated into the device 10, so that the test object (DUT) is electrically connected to the input 30 and the output 32 below the third critical temperature T43.

[0125] Preferably, in a fourth measurement below the third transition temperature T43, at least one electrical property of the test object DUT is measured.

[0126] This is preferably the same electrical property that was recorded in the previous three measurements. For example, the same scattering parameter, or the same two or more scattering parameters, are recorded in all four measurements.

[0127] The respective measured values ​​of the individual measurements are then preferably used to determine, for example, a calibration value of the test object DUT or an error correction, for example due to systematic disturbances in the arrangement.

[0128] This allows the electrical behavior of the test object (DUT) to be precisely measured using the analysis unit 50. The systematic errors in the electrical measurement of the test object due to influences from the arrangement 20 can be determined and corrected using the three measurements of the three standards. Consequently, the method is suitable for high-precision measurements.

[0129] The arrangement 20 is preferably configured as in one of the embodiments described above. The method can, for example, comprise a two-port measurement, in which the arrangement comprises two arrangements, each with three superconductors, and the two arrangements are implemented, for example, as described above. In this case, the analysis unit 50 is preferably configured for two-port measurement. In this case, the test object DUT is preferably arranged between the output 32 of the first arrangement 20 and the output of the second arrangement.

[0130] The method may comprise a multi-port measurement, wherein preferably six of the superconductors are arranged and connected in accordance with the two-port measurement as described above, and the analysis unit 50 is designed for multi-port measurement.

[0131] An eleventh example relates to method 12 of example 10, wherein the electrical property comprises at least one scattering parameter of the device 20 and / or the device under test DUT.

[0132] A twelfth example relates to a method 12 according to one of examples 10 to 11, wherein the first, second, third and fourth measurements 81, 82, 83, 84 comprise applying 100 an alternating current signal AC, preferably with a frequency f above 10 kHz, to the arrangement 20 and during and / or after the application 100: detecting 110 a signal response A of the arrangement 20 to the applied alternating current signal AC, wherein the application 100 takes place before, during and / or after falling below one of the transition temperatures T41, T42, T43.

[0133] As a result, the electrical behavior of the arrangement 20 and / or the test object DUT can be determined as a function of frequency. For example, the applied alternating current signal comprises multiple frequency components, changes frequency over time, and / or multiple signals with different frequencies are applied one after the other. The respective signal response to the applied signal is recorded by the analysis unit 50. Preferably, the analysis unit 50 determines the at least one electrical property of the arrangement 20 and / or the test object DUT from the applied signal and the signal response. For example, the analysis unit DUT determines a frequency-dependent attenuation, amplification, phase shift, and / or frequency shift. Various signal shapes are possible, for example sinusoidal signals, sawtooth signals, square-wave signals, combinations of several of these signal shapes, combinations of several signals of the same shape with different frequencies, or other signal shapes.

[0134] If the application occurs while one of the transition temperatures T41, T42, T43 is undershot, the step response of the superconductor 41, 42, 43, to which the transition temperature T41, T42, T43 belongs, is measurable.

[0135] The method offers particular advantages for measuring high-frequency properties of electrical components in complex electrical arrangements 20 at low temperatures. The described combination of superconductors 41, 42, 43 and standards N1, N2, N3 enables calibration without additional control lines and the resulting heat input. Furthermore, highly precise measurement of the high-frequency properties is possible, since calibration using superconductors makes it possible to determine and correct the systematic influences and unknown parameters of the electrical arrangement.

[0136] A thirteenth example relates to a method for calibrating a device 10 for measuring at least one electrical property of an electrical arrangement (20) according to one of examples one to nine, comprising the steps: a) first measurement 81 of the at least one electrical property of the arrangement 20 at a temperature above the first critical temperature T41, wherein the arrangement serves as the first standard N1; b) first cooling 71 of the arrangement 20 below the first critical temperature T41 and above the second critical temperature T42, such that when the temperature falls below the first critical temperature T41, a first offset length L1 of the arrangement 20 results and the arrangement 20 serves as the second standard N2; c) after the first cooling 71: second measurement 81 of the at least one electrical property of the arrangement 20;d) after the second measurement 81: second cooling 72 of the arrangement 20 to a temperature between the second transition temperature T42 and the third transition temperature T43, so that the arrangement 20 changes the electrical connection between the second standard N2 and a third standard N3 due to a switching of the second superconductor 42 into the superconducting state and the arrangement (20) serves as the third standard N3; e) after the second cooling 72: third measurement 82 of the at least one electrical property of the arrangement 20, f) after the third measurement 82: third cooling 73 of the arrangement 20 to a temperature below the third transition temperature T43, so that the arrangement 20 changes the electrical connection between the third standard N3 and the test object DUT due to a switching of the third superconductor 43 into the superconducting state, so that the arrangement 20 serves as the test object DUT;g) after the third cooling 73: fourth measurement 83 of the at least one electrical property of the arrangement 20; and h) calculation 90 of at least one further electrical property of the arrangement 20 based on the measurements of the at least one electrical property. List of reference symbols;

[0137] 10 Device

[0138] 12 procedures

[0139] 20 electrical arrangement

[0140] 22 second electrical arrangement

[0141] 30 Receipt of the order

[0142] 31 Connection for the test object

[0143] 32 Outcome of the order

[0144] 33 first goal

[0145] 34 second goal

[0146] 41 , 42, ... first, second, ... superconductor

[0147] 50 analysis units

[0148] 60 cooling unit

[0149] 71 , 72, 73 first, second, third cooling

[0150] 81 , 82, 83, 84 first, second, third, fourth measurement

[0151] 90 Calculating another electrical property

[0152] 100 Applying an alternating current signal

[0153] 110 Capturing a Signal Response

[0154] A signal response

[0155] AC alternating current

[0156] DUT test object f frequency

[0157] L1, L2, L3, L4 first, second, third, fourth offset length

[0158] N1 , N2, N3, Ni first, second, third, i-th normal

[0159] T Temperature

[0160] T41 , T42... , Ti first, second ... , i-th transition temperature

Claims

Patent claims 1. Temperature-dependent switchable high-frequency circuit (20) for use in a calibration of an analysis unit (50) for high-frequency signals, wherein the high-frequency circuit (20) has the following: a) an input (30); b) a first standard (N1); c) a second standard (N2); d) a third standard (N3); e) a first superconductor (41) with a first transition temperature (T41); f) a second superconductor (42) with a second transition temperature (T42); g) a third superconductor (43) with a third transition temperature (T43), h) wherein the transition temperatures (T41, T42, T43) are each different from one another, i) wherein above the transition temperatures (T41, T42, T43) the first Standard (N1) is electrically connected to the input (30), i. so that a property of the first standard (N1) is measurable; j) by falling below a first transition temperature (T41 ) the second Standard (N2) is electrically connected to the input (30), i. so that a property of the second standard (N2) is measurable k) by falling below a second transition temperature (T42) the third Standard (N3) is electrically connected to the input (30), i. so that a property of the third standard (N3) can be measured, and l) when a third transition temperature is undershot, a connection for a test object (DUT) is electrically connected to the input (30), i. so that a property of the test object (DUT) can be measured.

2. High-frequency circuit (20) according to claim 1, wherein only the second standard (N2) is electrically connected to the input (30) when the temperature falls below the first transition temperature (T41) and is above the second transition temperature (T42).

3. High-frequency circuit (20) according to one of the preceding claims, wherein only the third standard (N3) is electrically connected to the input (30) when the temperature falls below the second transition temperature (T42) and is above the third transition temperature (T43).

4. High-frequency circuit (20) according to one of the preceding claims, wherein by falling below the third transition temperature (T43) only the terminal for the test object (DUT) is electrically connected to the input (30).

5. High-frequency circuit (20) according to one of the preceding claims, wherein at least one of the superconductors (41, 42, 43) is designed as a changeover switch, so that depending on a temperature of the high-frequency circuit (20) and the corresponding transition temperature (T41, T42, T43) of the at least one superconductor (41, 42, 43), only a single standard (N1, N2, N3) or test object (DUT) is electrically connected to the input.

6. High-frequency circuit (20) according to claim 5, wherein the first superconductor (41), the second superconductor (42) and the third superconductor (43) are designed as changeover switches.

7. High-frequency circuit (20) according to claim 1, wherein by falling below the first transition temperature (T41) and above the second transition temperature (T42), the first standard (N1) and the second standard (N2) are electrically connected to the input (30).

8. High-frequency circuit (20) according to claim 1 or 7, wherein Below the second transition temperature (T42) and above the third transition temperature (T43), the first standard (N1), the second standard (N2) and the third standard (N3) are electrically connected to the input (30).

9. High-frequency circuit according to one of claims 1, 7 and 8, wherein If the third transition temperature (T43) is undershot, the first standard (N1), the second standard (N2), the third standard (N3) and the connection for the test object (DUT) are electrically connected to the input (30).

10. High-frequency circuit according to one of the preceding claims, wherein the first standard (N1), second standard (N2) and third standard (N3) are each different from one another at least with respect to one electrical property.

11. A method for calibrating an analysis unit (50) for measuring at least one electrical property of a test object (DUT) by means of a temperature-dependent switchable high-frequency circuit (20) according to one of the preceding claims, comprising the steps: a) measuring a first electrical property of the first standard (N1) above the first transition temperature (T41); b) measuring a second property of the second standard (N2) below the first transition temperature (T41) and above the second transition temperature (T42); c) measuring a third electrical property of the third standard (N2) below the second transition temperature (T41) and above the third transition temperature (T42) d) calibrating the analysis unit (50) based on at least the first, second and third electrical properties; e) measuring the at least one electrical property of the Test object (DUT) using the calibrated analysis unit (50) below the third transition temperature (T43).

12. The method according to claim 11, wherein the respective measuring comprises the following steps: i) applying (100) an alternating current signal (AC), preferably with a frequency (f) above 10 kHz, to the input (30) and (ii) during and / or after application (100): recording (110) a Signal response (A) of the high-frequency circuit (20) to the applied alternating current signal (AC) at the input (30), iii) wherein the application (100) occurs before, during and / or after falling below one of the transition temperatures (T41, T42, T43).

13. The method according to any one of claims 11 and 12, wherein the method further comprises the following step: a) changing a temperature of the high-frequency circuit (20) between an uppermost transition temperature of the superconductors (41, 42, 43) and a lowermost transition temperature of the superconductors (41, 42, 43).

Images