A saturable energy-controllable superconducting transition edge sensor and a manufacturing method thereof

Abstract

The application relates to a superconducting transition edge sensor capable of regulating saturated energy, comprising: an absorber; two or more TES films, all of which are arranged in order and connected directly or indirectly; at least one TES film is connected with the absorber; the saturated energy of each TES film corresponding to the superconducting transition edge sensor is different; each TES film is connected with a signal reading circuit; and a heat sink is weakly connected with the at least one TES film. The application has the beneficial effect that, compared with a single TES film superconducting transition edge sensor, the application can realize large dynamic range measurement without losing the low-energy photon detection energy resolution.

Description

Technical Field

[0001] This application belongs to the field of sensor technology, and in particular relates to a superconducting transition edge sensor with adjustable saturation energy and its fabrication method. Background Technology

[0002] Superconducting transition edge sensors (TES) can be used for energy detection of X-rays, gamma rays, etc., utilizing the transition of a superconducting thin film from a superconducting state with zero resistance to a state with resistance R. n The resistance is sensitive to temperature during the normal state transition to detect the energy of incident X-rays, gamma rays, etc.

[0003] like Figure 1 As shown, TES consists of an absorber, a TES film, weak links, a heat sink, etc.

[0004] Its working principle is as follows:

[0005] like Figure 2 As shown, the normal-state resistance of a superconductor is R. n The resistance in the superconducting state is 0. When the resistance R of the superconductor is at the superconducting transition edge, i.e., 0... <R<R n At this time, there is a one-to-one correspondence between resistance and temperature. Before measuring the incident photon energy, the resistance R of the TES thin film is biased to 0 by the test circuit. <R<R n At the superconducting transition edge, the heat sink temperature is lower than the bias operating point temperature of the TES film. The photon to be measured (energy E) is incident on the absorber and absorbed. The absorber converts all the energy carried by the photon into heat energy, causing the absorber temperature to rise. The heat is transferred to the TES film, causing the TES film temperature to rise. During this process, the resistance of the TES film also increases with the temperature. Subsequently, the heat from the absorber and the TES film is transferred to the heat sink through a weak connection, and the temperature of the TES film returns to the bias operating point, ready for the next measurement.

[0006] When the test circuit and the superconducting transition edge detector are determined, the energy E of the incident photon and the peak temperature T of the TES thin film during the detection process are... p One-to-one correspondence. The peak value R of the TES thin film resistance change during each measurement is read using the test circuit. p When R p =R n At this point, the TES film is in its normal state, and the TES film is saturated, indicating that the incident photon energy E exceeds the dynamic range measured by the superconducting transition edge sensor. When R... <R p <R n At that time, the peak temperature k of the TES film in this test p With R pThe corresponding relationship between them is given by the curve of the resistance of the TES thin film versus temperature in the superconducting transition process.

[0007] In summary, in the process of measuring the incident photon energy, the incident photon energy E and the peak temperature T of the TES thin film p There is a one-to-one correspondence when R p <R n , the peak resistance change R p of the TES thin film and the peak temperature T p of the TES thin film are one-to-one corresponding. Therefore, in the dynamic range of TES energy measurement, the peak resistance change R p of the TES thin film and the incident energy E are one-to-one corresponding. Conclusion: the incident photon energy E can be obtained by measuring the resistance of the TES thin film.

[0008] The parameters for evaluating the performance of the superconducting transition edge sensor are energy resolution and saturation energy; the energy resolution of the superconducting transition edge sensor is:

[0009]

[0010] In practical applications, the smaller the ΔE is, the higher the accuracy of the measurement result is. In the above formula, k B is the Boltzmann constant, T is the working point temperature, C is the heat capacity of the superconducting transition edge sensor, and α represents the sensitivity coefficient of the resistance to the temperature.

[0011] Saturation energy:

[0012]

[0013] The problem of the superconducting transition edge sensor is that the superconducting transition edge of the TES thin film is narrow, which makes the measurable dynamic range of the photon energy very small. The saturation energy is related to the heat capacity C of the superconducting transition edge sensor, the superconducting transition temperature T c of the TES thin film, the working point temperature T and the sensitivity coefficient α of the TES thin film resistance to the temperature.

[0014] According to It can be seen that the energy resolution and the saturation energy are related to each other; when researchers try to increase the saturation energy of the superconducting transition edge sensor to detect incident photons with larger energy, the energy resolution ΔE (the smaller the better) will inevitably be increased, and the energy resolution of the TES for low-energy photon measurement will be lost. SUMMARY

[0015] The technical problems solved by the present application are: to solve the problems in the prior art that the energy resolution of a superconducting transition edge sensor is sacrificed to improve the dynamic range of energy measurement, and to provide a superconducting transition edge sensor with adjustable saturation energy and a manufacturing method thereof.

[0016] The technical solutions adopted by the present application to solve the technical problems are:

[0017] A superconducting transition edge sensor with adjustable saturation energy comprises:

[0018] an absorber;

[0019] two or more TES films, which are arranged in order and connected directly or indirectly, at least one TES film is thermally connected to the absorber, and the T c , alpha and size do not need to be the same, and each TES film is connected to a signal readout circuit;

[0020] a heat sink, which is weakly connected to at least one TES film;

[0021] The TES film comprises a first TES film, a second TES film, a (n-1)-th TES film, and an nth TES film, n is the serial number of the TES film, and is a natural number greater than 1.

[0022] Preferably, in the superconducting transition edge sensor with adjustable saturation energy, the upper surface of the first TES film is thermally connected to the absorber, the lower surface of the (n-1)-th TES film is thermally connected to the upper surface of the nth TES film, and the lower surface of the nth TES film is weakly connected to the heat sink.

[0023] Preferably, in the superconducting transition edge sensor with adjustable saturation energy, the upper surface of the first TES film is thermally connected to the absorber, the edge of the (n-1)-th TES film is thermally connected to the edge of the nth TES film, and the lower surface of each TES film is weakly connected to the heat sink.

[0024] Preferably, in the superconducting transition edge sensor with adjustable saturation energy, the upper surface of each TES film is thermally connected to the absorber, there is no thermal connection between all the TES films, and the lower surface of each TES film is weakly connected to the heat sink.

[0025] A superconducting transition edge sensor with adjustable saturation energy is formed by combining any two or three of the above sensors.

[0026] Preferably, in the superconducting transition edge sensor with adjustable saturation energy, each TES film has a regular shape.

[0027] The application discloses a method for manufacturing a superconducting transition edge sensor with adjustable saturation energy, and belongs to the technical field of superconducting transition edge sensor.

[0028] S1, providing two or more TES films, according to the relationship of ΔE, E sat and C, T, α, by adjusting the material, preparation process and size of each TES film, T c , α, C TES are obtained.

[0029] ΔE is the energy resolution of the superconducting transition edge sensor related to the corresponding TES film, E sat is the saturation energy of the superconducting transition edge sensor related to the corresponding TES film, C is the heat capacity of the superconducting transition edge sensor related to the corresponding TES film, C TES is the heat capacity of the corresponding TES film, T is the working point temperature, T c is the superconducting transition temperature related to T, and α is the sensitivity coefficient of the TES film to temperature, wherein C TES is a component of C.

[0030] S2, using the TES films obtained in S1, sequentially arranging and connecting the TES films to obtain the superconducting transition edge sensor with adjustable saturation energy.

[0031] Preferably, the method for manufacturing the superconducting transition edge sensor with adjustable saturation energy changes the method for changing the saturation energy of the superconducting transition edge sensor with adjustable saturation energy, and the method comprises: changing the heat connection mode between the TES film and the absorber.

[0032] Preferably, the method for manufacturing the superconducting transition edge sensor with adjustable saturation energy changes the method for changing the saturation energy of the superconducting transition edge sensor with adjustable saturation energy, and the method comprises: changing the heat connection mode between the TES film and the heat sink.

[0033] Preferably, the method for manufacturing the superconducting transition edge sensor with adjustable saturation energy changes the method for changing the saturation energy of the superconducting transition edge sensor with adjustable saturation energy, and the method comprises: changing the superconducting transition temperature of the TES film or changing the sensitivity coefficient of the TES film to temperature.

[0034] The application has the following beneficial effects:

[0035] Compared with a single TES film superconducting transition edge sensor, the superconducting transition edge sensor with adjustable saturation energy can realize large dynamic range detection without substantially losing the energy resolution for detecting low-energy photons. In theory, compared with a single TES film, multiple TES films can introduce more heat capacity to the measurement system, but the heat capacity C TESThe heat capacity of the superconducting transition edge sensor is much smaller than the heat capacity of the superconducting transition edge sensor, so increasing the number of TES films will reduce the energy resolution, but the impact is minimal. BRIEF DESCRIPTION OF DRAWINGS

[0036] The technical solutions of the present application are further described below in conjunction with the drawings and examples.

[0037] Figure 1 is a schematic diagram of the structure of the existing superconducting transition edge sensor;

[0038] Figure 2 is a schematic diagram of the resistance-temperature curve of the TES film of the superconducting transition edge sensor during phase transition;

[0039] Figure 3 is a schematic diagram of the adjustable saturated energy superconducting transition edge sensor structure of embodiment 1 of the present application;

[0040] Figure 4 is a schematic diagram of the adjustable saturated energy superconducting transition edge sensor structure of embodiment 2 of the present application;

[0041] Figure 5 is a schematic diagram of the adjustable saturated energy superconducting transition edge sensor structure of embodiment 3 of the present application. DETAILED DESCRIPTION

[0042] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0043] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore it cannot be understood as a limitation on the scope of protection of the present application. In addition, the terms "first", "second" and the like are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features limited by "first", "second" and the like can explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified, the meaning of "a plurality of" is two or more.

[0044] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connection", "linking" should be understood in a broad sense, for example, it can be fixed connection, or detachable connection, or integral connection; it can be mechanical connection, or electrical connection; it can be direct connection, or indirect connection through intermediate medium, or internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0045] The technical solutions of the present application will be described in detail below with reference to the drawings and in combination with the embodiments.

[0046] Embodiment 1

[0047] The present embodiment provides a superconducting transition edge sensor capable of regulating saturated energy, as shown in the formula (I), comprising: Figure 3

[0048] An absorber;

[0049] Two or more TES films, all of which are arranged in order and connected directly or indirectly; at least one TES film is thermally connected to the absorber; each TES film has a T c , α and size do not need to be the same, and each TES film is connected with a signal readout circuit;

[0050] A heat sink, which is weakly connected to at least one TES film;

[0051] The TES film includes a first TES film, a second TES film,..., an (n-1)th TES film, and an nth TES film, where n is the serial number of the TES film and is a natural number greater than 1.

[0052] The upper surface of the first TES film is thermally connected to the absorber, the lower surface of the (n-1)th TES film is thermally connected to the upper surface of the nth TES film, and the lower surface of the nth TES film is weakly connected to the heat sink.

[0053] There is thermal contact between the first TES film and the nth TES film. The incident photon energy obtained by the absorber needs to pass through each TES film to reach the heat sink, and the size, heat capacity C TES , superconducting transition temperature T c , and α of each TES film do not need to be consistent.

[0054] In calculating the saturated energy of each TES film, the corresponding heat capacity is the same, i.e. C1=C2=...=C n The design and preparation of each TES film are different, so that the corresponding working point temperature T and the sensitivity coefficient α of the resistance changing with temperature are different, i.e. T1≠T2≠...≠T​n , α1≠α2≠...≠α n , very easy to achieve E sat_1 ≠E sat_2 ≠...≠E sat_n .

[0055] The superconducting transition edge sensor with adjustable saturation energy provided by the embodiment, compared with the superconducting transition edge sensor structure of the prior art in which each detection unit has only one TES film, provides a scheme in which multiple TES films constitute a superconducting transition edge sensor. The scheme can adjust the superconducting transition temperature T c and the value of α of the TES film in relation to the working point temperature T by changing the design and preparation process of each TES film. c Through the control of the parameters T n , α, the dynamic range of energy measurement of the superconducting transition edge sensor can be adjusted.

[0056] Each TES film is connected with a signal readout circuit. When analyzing the energy resolution and saturation energy of the superconducting transition edge sensor corresponding to one of the TES films, the other TES films can be considered as absorbers or weakly connected parts as appropriate, or not considered in the analysis, etc.

[0057] Suppose that there are n TES films in the superconducting transition edge sensor with adjustable saturation energy, and the working point temperatures are T1, T2,..., T n , and the values of α are α1, α2,..., α n The corresponding heat capacities when calculating the saturation energy of each TES film are C1, C2,..., C n The saturation energy of the superconducting transition edge sensor is The saturation energy of the superconducting transition edge sensor corresponding to each TES film can be calculated as: The energy resolution is

[0058] Therefore, the superconducting transition edge sensors with different saturation energies correspond to different energy resolutions. In this way, the energy resolution and saturation energy of the superconducting transition edge sensors corresponding to different TES films are not the same. Compared with the superconducting transition edge sensor with a single TES film, in order to achieve a large dynamic measurement range, the energy resolution for measuring low-energy photons must be sacrificed.

[0059] In the design and preparation process of the TES film, it is easy to prepare TES films with different superconducting transition temperatures and different temperature-sensitive coefficients of resistance.

[0060] Therefore, in the structural design and fabrication of superconducting transition edge sensors with tunable saturation energy, it is easy to achieve different saturation energies for superconducting transition edge sensors corresponding to different TES thin films, i.e., E0. sat_1 ≠E sat_2 ≠...≠E sat_n This achieves the goal of dynamic range control for energy measurement.

[0061] Example 2

[0062] This embodiment provides a superconducting transition edge sensor with adjustable saturation energy, such as... Figure 4 As shown, it includes:

[0063] A single absorber;

[0064] Two or more TES films, all TES films are arranged in an orderly manner and directly or indirectly connected; at least one TES film is thermally connected to the absorber; the T of each TES film is... c The α and size do not need to be the same, and each TES film is connected to a signal readout circuit;

[0065] The heat sink is weakly connected to at least one layer of TES film.

[0066] TES films include the 1st TES film, the 2nd TES film, ..., the (n-1)th TES film, and the nth TES film, where n is the sequence number of the TES film, which is a natural number greater than 1.

[0067] The upper surface of the first TES film is thermally connected to the absorber, the edge of the (n-1)th TES film is thermally connected to the edge of the nth TES film, and the lower surface of each TES film is weakly connected to the heat sink.

[0068] like Figure 4 As shown, in this embodiment, there is thermal contact between the first TES and the nth TES. Each TES film is directly and weakly connected to the heat sink. Thus, the heat reaching the i-th TES film must pass through all the preceding TES films. The size, heat capacity, superconducting transition temperature, and α value of each TES film can be the same or different.

[0069] The heat capacity corresponding to each TES thin film is different when calculating the saturation energy, that is, C1≠C2≠...≠C n Regardless of whether the design and fabrication of each TES film are the same, it is easy to achieve E sat_1 ≠E sat_2 ≠...≠E sat_n .

[0070] Example 3

[0071] The embodiment provides a superconducting transition edge sensor with adjustable saturation energy, which comprises the following components as shown in the figure: Figure 5

[0072] an absorber;

[0073] two or more TES films, which are arranged in order and connected directly or indirectly, at least one of the TES films is connected with the absorber, and each TES film has a T c , α and size, and each TES film is connected with a signal readout circuit;

[0074] a heat sink, which is weakly connected with at least one of the TES films;

[0075] The TES films comprise a first TES film, a second TES film, a (n-1)th TES film and an nth TES film, wherein n is the serial number of the TES film and is a natural number greater than 1.

[0076] The upper surface of each TES film is connected with the absorber, the TES films are not connected with each other, and the lower surface of each TES film is weakly connected with the heat sink.

[0077] As shown in the figure, in the embodiment, each TES film is connected with the absorber, each TES film is kept in thermal contact with the heat sink through weak connection, but the TES films are not directly connected with each other, and the size, heat capacity, superconducting transition temperature and α of each TES film are not required to be consistent. Figure 5

[0078] If the thermal connection between the absorber and each TES film is consistent, the residual heat capacity of each TES film corresponding to the TES film itself heat capacity C TES , α and C c of each TES film are consistent, and the TES films can be prepared by adjusting the T TES , α and C sat_1 of each TES film. sat_2 . sat_n .

[0079] Embodiment 4

[0080] The embodiment provides a superconducting transition edge sensor with adjustable saturation energy, which is formed by combining any two of the sensors in the embodiments 1, 2 and 3 or by combining all the three sensors.

[0081] Preferably, the combined sensor can share the absorber and the heat sink.

[0082] ​​With the above ideal embodiments according to the present application as the inspiration, through the above description, relevant staff can make various changes and modifications without deviating from the scope of the technical idea of the present application. The technical scope of the present application is not limited to the content of the specification, and the technical scope must be determined according to the scope of claims.

Claims

1. A saturating energy-regulated superconducting transition edge sensor, comprising: It comprises: an absorbing body; n layers of TES films, n is a natural number greater than 1, all the TES films are arranged in order and connected directly or indirectly; the n layers of TES films are connected with the absorbing body as a whole; n signal readout circuits, corresponding to the n layers of TES films, for independently reading out the resistance change signals of each layer of TES films; a heat sink, weakly connected with at least one layer of TES films; wherein the n layers of TES films are arranged with different sizes, and / or different superconducting transition temperatures Tc, and / or different temperature sensitivity coefficients α, and / or different superconducting transition edge sensor heat capacities C, so that the corresponding saturation energies Esat of each layer of TES films are different, thereby controlling the energy detection dynamic range of the sensor by selecting the readout signals of different TES films.

2. The controllably saturated energy superconducting transition edge sensor of claim 1, wherein, The upper surface of the first TES film is connected with the absorbing body, the lower surface of the n-1th TES film is connected with the upper surface of the nth TES film, and the lower surface of the nth TES film is weakly connected with the heat sink.

3. The controllably saturated energy superconducting transition edge sensor of claim 1, wherein, The upper surface of the first TES film is connected with the absorbing body, the edge of the n-1th TES film is connected with the edge of the nth TES film, and the lower surface of each TES film is weakly connected with the heat sink.

4. The controllably saturated energy superconducting transition edge sensor of claim 1, wherein, The upper surface of each TES film is connected with the absorbing body, and there is no thermal connection between all the TES films, and the lower surface of each TES film is weakly connected with the heat sink.

5. A saturating energy-regulated superconducting transition edge sensor, comprising: Any two or three of the sensors described in claims 2-4 are combined.

6. The saturating energy-regulated superconducting transition edge sensor of any of claims 1-5, wherein, The shape of each TES film is a regular shape.

7. A method of fabricating a saturating energy-regulatable superconducting transition edge sensor, comprising: It comprises the following steps: S1, providing two or more TES films, according to ΔE, E sat The relationship between C, T, and a is obtained by adjusting the material, preparation process, and size of each TES film c , a, C TES No need for the same TES film; ΔE is the energy resolution of the superconducting transition edge sensor associated with the corresponding TES thin film, E sat C is the saturation energy of the superconducting transition edge sensor associated with the corresponding TES thin film, TES C is the heat capacity of the corresponding TES thin film, T is the operating point temperature, c Tc is the superconducting transition temperature associated with T, and a is the sensitivity coefficient of the TES thin film to temperature, where TES C is a component of C; S2, using the TES film obtained in S1, arranging and connecting in order to obtain a superconducting transition edge sensor with adjustable saturation energy according to any one of claims 1-5.

8. The method of claim 7, wherein the superconducting transition edge sensor is a controllably saturated energy superconducting transition edge sensor. The method for changing the saturation energy of the superconducting transition edge sensor with adjustable saturation energy comprises changing the thermal connection mode between the TES film and the absorbing body.

9. The method of claim 7 or 8, wherein the superconducting transition edge sensor is a controllably saturated energy superconducting transition edge sensor. The method for changing the saturation energy of the superconducting transition edge sensor with adjustable saturation energy comprises changing the thermal connection mode between the TES film and the heat sink.

10. The method of claim 7-9, wherein the method further comprises: The method for changing the saturation energy of the superconducting transition edge sensor with adjustable saturation energy comprises changing the superconducting transition temperature of the TES film or changing the temperature sensitivity coefficient of the TES film.

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