Electronic device and quantum computer system

Abstract

An electronic device (1) for controlling a capacitive load (15) is specified, with - an inductor (2) and - a variable capacitor (3) which is electrically connected to the inductor (2), wherein - the inductance (2) comprises a superconducting material, and - the variable capacitor (3) is designed to change its capacitance. Furthermore, a quantum computer system (21) is specified.

Description

[0001] The present disclosure relates to an electronic device and a quantum computing system.

[0002] One possible solution for achieving an AC voltage oscillating at radio frequencies, typically in the MHz range, to drive a capacitive load typically involves coupling the capacitive load to a typical radio frequency resonator, which has a predominantly inductive reactance, to utilize a resonant voltage buildup within the radio frequency resonator. A common approach is to use typical spiral resonators made of an electrical conductor such as copper.

[0003] However, if the typical radiofrequency resonator is placed outside a cryostat and the capacitive load is placed inside a cryostat, there is a parasitic capacitance of the capacitive load and an ohmic resistance of the wires between the typical radiofrequency resonator outside the cryostat and the capacitive load. The parasitic capacitance and ohmic resistance reduce the quality factor of the typical radiofrequency resonator.

[0004] If the typical radio frequency resonator is located in the cryostat, this can be problematic at typical radio frequencies due to space constraints. Furthermore, heat dissipation in a cryostat is much more problematic.

[0005] Furthermore, when operating the capacitive load at cryogenic temperatures, changes in material resistance and geometry can significantly shift the linear electrical response of typical radiofrequency resonator components, making impedance matching of a radiofrequency source to a typical radiofrequency resonator difficult. The result is either that most of the radiofrequency power is reflected, rendering the capacitive load inoperable, or that a shift in the electrical response at room temperature must be pre-compensated, resulting in time-consuming iteration over many cooling cycles of the entire system.

[0006] One problem to be solved is to provide an electronic device having improved electronic properties. Furthermore, a quantum computer system comprising such an electronic device is to be provided.

[0007] The problem is solved by the subject matter of the independent claims. Advantageous embodiments, implementations, and further developments are the subject matter of the respective dependent claims.

[0008] The electronic device for driving a capacitive load is described. In particular, the electronic device is designed to be arranged in a cryostat. The capacitive load is arranged, for example, inside the cryostat or outside a cryostat. The electronic device is, for example, a passive electronic device. In particular, unlike an active electronic device, the passive electronic device does not generate power. This means that the passive electronic device cannot amplify the power of a signal, but the passive electronic device can increase the voltage or current of a signal. The passive electronic device is, for example, an oscillating circuit such as a resonator.

[0009] The capacitive load includes, for example, another electronic device, such as an ion trap. The capacitive load includes, for example, several electrically conductive elements. This means that the capacitive load has, for example, a parasitic capacitance. The parasitic capacitance arises, in particular, from the proximity of the electrically conductive elements of the capacitive load.

[0010] The electronic device is designed in particular to control an ion trap in a cryostat.

[0011] The cryostat is designed, for example, to provide a cryogenic environment. The electronic device and / or the capacitive load are arranged, in particular, within the cryogenic environment. The cryostat, in particular the cryogenic environment, is designed to cool the electronic device and / or the capacitive load to a maximum of 50 K or a maximum of 30 K and / or at least 0.1 mK or at least 0.3 mK.

[0012] According to at least one embodiment, the electronic device comprises an inductor. The inductor is, in particular, a passive electronic component of the passive electronic device. The inductor is designed, for example, to store and release electrical energy. By way of example, the inductor is formed with a wire. In particular, the wire extends along a curve that starts from a central part of the inductor and, as it circles around the central part, continues to extend to an end part. The strength of a magnetic field generated by the inductor, which is, in particular, characteristic of an inductance value, depends, for example, on a number of turns of the inductor, a diameter of the inductor, and a material of the inductor. The diameter of the inductor depends, for example, on a dielectric substrate of the inductor.The number of turns is, for example, at least 3 and at most 50, e.g., about 10. The inductance has, for example, a predetermined inductance value of at least 0.001 µH or at least 0.1 µH and / or at most 50 µH or at most 10 µH, e.g., about 3 µH.

[0013] According to at least one embodiment, the electronic device comprises a variable capacitor electrically connected to the inductor. For example, the variable capacitor is electrically connected to the central part of the inductor.

[0014] For example, the inductance, the variable capacitor, and the capacitive load form the oscillating circuit, i.e., the resonator. The oscillating circuit can be supplied with an alternating voltage.

[0015] According to at least one embodiment of the electronic device, the inductor comprises a superconducting material. The superconducting material is configured, for example, to conduct an electric current without resistance below a critical temperature. The superconducting material has, for example, a critical temperature of at least 3 K, at least 5 K, or at least 10 K.

[0016] According to at least one embodiment of the electronic device, the variable capacitor is configured to change its capacitance. A DC voltage can be supplied to the variable capacitor. In particular, the variable capacitor can be adjusted or varied within a predetermined capacitance value range depending on the DC voltage. The predetermined capacitance value range can be at least 0.1 pF or at least 1 pF and / or at most 10 nF, at most 1 nF, or at most 500 pF, e.g., approximately 15 pF.

[0017] One idea, among others, is to form the resonant circuit of the electronic device with the superconducting inductor and the variable capacitor. Advantageously, such a resonant circuit can spectrally filter unwanted sideband noise from an AC voltage supplied to the resonant circuit. The negligible ohmic losses of the superconducting material of the inductor enable a compact design of the inductor for installation in a cryostat. Furthermore, the superconducting material of the inductor ensures a high quality factor of the resonant circuit—even in the presence of a comparatively large parasitic capacitance of the capacitive load. Advantageously, impedance matching of the supplied AC voltage to the resonant circuit is achieved by adjusting the variable capacitor via the supplied DC voltage.

[0018] According to at least one embodiment of the electronic device, a first input is electrically connected to a first node, to which the inductor and the variable capacitor are electrically connected. In particular, the node electrically connects the first input, the inductor, and the variable capacitor to one another.

[0019] The first input is designed, for example, to provide the oscillating circuit with an alternating voltage oscillating at radio frequencies. The radio frequency is, for example, at least 1 MHz and at most 200 MHz, e.g., approximately 20 MHz. For example, the alternating voltage is provided by an external alternating voltage source.

[0020] According to at least one embodiment of the electronic device, a second input is electrically connected to the variable capacitor in order to provide a DC voltage to the variable capacitor via a DC voltage source. For example, the second input is configured to provide the DC voltage to the variable capacitor. In particular, the second input is configured to be electrically connected to a further signal line connected to the DC voltage source.

[0021] According to at least one embodiment of the electronic device, an output is electrically conductively connected to the inductor. For example, the output is electrically conductively connected to the end part of the inductor.

[0022] In particular, the first input, the second input, and / or the output are included in the electronic device. For example, the first input, the second input, and / or the output each comprise a connection interface.

[0023] According to at least one embodiment of the electronic device, the first input is designed to be electrically conductively connected to a first signal line connected to an AC voltage source. The first input is electrically conductively connected to the first signal line, in particular via the connection interface.

[0024] According to at least one embodiment of the electronic device, the output is designed to be electrically conductively connected to a second signal line connected to the capacitive load. The output is electrically conductively connected to the second signal line, in particular via the connection interface. Alternatively, the output itself is a signal line that is integrally connected to the second signal line.

[0025] Each of the signal lines is designed to transmit a voltage, in particular an alternating voltage.

[0026] According to at least one embodiment of the electronic device, the inductor comprises a superconducting alloy that includes at least the superconducting material. The superconducting alloy comprises, for example, at least two different materials.

[0027] According to at least one embodiment of the electronic device, the superconducting alloy comprises at least two of the elements barium, copper oxide, yttrium, strontium, titanium, magnesium, boron, and niobium. For example, the superconducting alloy comprises or consists of yttrium-barium-copper oxide.

[0028] According to at least one embodiment of the electronic device, the superconducting alloy has a critical temperature of at least 30 K. For example, the superconducting alloy has a critical temperature of at least 35 K, at least 39 K, or at least 40 K. In addition, the inductance with the superconducting alloy has a critical current density of at most 10 9 A / cm 2 or a maximum of 10 7 A / cm 2 and / or at least 10 3 A / cm 2 or at least 10 5 A / cm 2 , about 2*10 6 A / cm 2, is. The critical current is the maximum current that can be carried by the inductor without resistance.

[0029] According to at least one embodiment, the electronic device further comprises a dielectric substrate. The dielectric substrate is formed, for example, with sapphire or magnesium oxide. The dielectric substrate extends within a main extension plane in lateral directions that are perpendicular to a vertical direction. The dielectric substrate has, in plan view along the vertical direction, an outer shape that is circular, elliptical, or polygonal, such as a square outer shape or a quadrangular outer shape. A maximum extension of the dielectric substrate in lateral directions is, for example, at least 10 mm and / or at most 100 mm, e.g., approximately 40 mm or 25 mm. The maximum extension in lateral directions can be a diameter or a side length. An extension of the dielectric substrate in the vertical direction is, for example,at least 100 nm and / or at most 5 µm, about 350 nm or 1 µm.

[0030] Furthermore, the variable capacitor extends in lateral directions within a main extension plane, spaced apart from the inductor and the dielectric substrate. For example, the variable capacitor is provided on a carrier that extends in lateral directions. The carrier is, for example, a printed circuit board.

[0031] According to at least one embodiment of the electronic device, the inductor is arranged on the dielectric substrate. For example, the inductor is in direct and immediate contact with the dielectric substrate. The inductor has a maximum extension in lateral directions that is smaller than the maximum extension in lateral directions of the dielectric substrate. This means that the inductor completely overlaps with the dielectric substrate, for example, in lateral directions.

[0032] According to at least one embodiment of the electronic device, the inductor comprises at least one, in particular a single, planar wire. The planar wire is formed with the superconducting material, in particular the superconducting alloy. The planar wire extends, for example, in a common plane oriented in lateral directions. "Planar" means here and below that the planar wire has a length in lateral directions, a width in lateral directions, and a height in the vertical direction, where the height is, for example, at least two orders of magnitude smaller than the width and / or the length. In particular, the height is smaller, e.g., at least 50% smaller, than the extension of the dielectric substrate in the vertical direction. The width of the planar wire is, for example, at least 0.5 mm and at most 5 mm, e.g., approximately 1 mm.

[0033] The planar wire is covered, for example, with a coating. The coating comprises or consists of a precious metal, such as gold. The coating has a thickness that is, in particular, less than a skin depth due to the skin effect at the alternating voltage oscillating at the radio frequency specified above.

[0034] According to at least one embodiment of the electronic device, the planar wire has a spiral shape. The planar wire has the spiral shape, particularly in plan view. The spiral shape corresponds, for example, to the outer shape of the dielectric substrate. This means that the spiral shape is a circular spiral shape, an elliptical spiral shape, or a polygonal spiral shape, such as a rectangular spiral shape.

[0035] According to at least one embodiment of the electronic device, the inductance comprises at least one, in particular a single, wire. The wire is formed with the superconducting material, in particular the superconducting alloy.

[0036] According to at least one embodiment of the electronic device, the wire is wound around a coil former. For example, the wire is wound around the coil former with multiple turns. For example, the wire is evenly distributed along the coil former. For example, the coil former is configured to provide a mechanical support structure for the wire.

[0037] According to at least one embodiment of the electronic device, the variable capacitor comprises at least two first capacitors and at least two electronic switches, wherein each of the electronic switches is connected in series with one of the first capacitors and forms a segment, and the segments are connected in parallel to one another. This means that the variable capacitor comprises a switchable capacitor arrangement. The electronic switch is an electronic component that is designed in particular to control a current flow in an input direction and an output direction. In particular, N-bit capacitance control can be advantageously implemented by using N segments.

[0038] For example, the switches are each formed with a bidirectional electronic switch. The bidirectional electronic switch is, in particular, a metal-oxide-semiconductor field-effect transistor (MOSFET). Alternatively, the bidirectional electronic switch is a triode for alternating current, a TRIAC, or an electromechanical relay. This means that the bidirectional electronic switch can be switched depending on a gate DC voltage provided by the DC voltage source.

[0039] According to at least one embodiment of the electronic device, the variable capacitor comprises at least one varactor diode and a DC voltage source, wherein the DC voltage source is connected in parallel with the varactor diode. The varactor diode has, in particular, a pn junction. The pn junction can further have a capacitance dependent on the width of a space charge zone, which capacitance is, in particular, dependent on a DC voltage provided by the DC voltage source. This DC voltage is advantageously provided for controlling the capacitance of the varactor diode and thus for impedance matching between the first signal line and the capacitive load connected via the second signal line.

[0040] The variable capacitor comprises, for example, two varactor diodes. This means that the variable capacitor is formed with a varactor diode array. When two varactor diodes are connected in opposite directions, nonlinearity compensation can be advantageously achieved.

[0041] The varactor diode or varactor diode array comprises additional circuit elements, such as at least one additional inductor and at least one resistor. These additional circuit elements make it possible to connect the DC voltage source to the varactor diode and control the capacitance, while simultaneously leaving the oscillating AC voltage in the resonant circuit unaffected, as they are selected to be high-impedance. These additional circuit elements have the advantage of effectively shielding and isolating the DC voltage from the currents in the resonant circuit, to which the varactor diode belongs.

[0042] According to at least one embodiment, the electronic device comprises a housing, wherein the inductor and the variable capacitor are enclosed by the housing. In particular, the housing comprises an upper cover and a lower cover opposite the upper cover, both extending in lateral directions. The upper cover and the lower cover are connected by at least one side cover of the housing. The first input, the second input, and / or the output are arranged and embedded within at least one cover. In particular, the first input, the second input, and / or the output completely penetrate the housing.

[0043] According to at least one embodiment of the electronic device, the housing comprises an electrically conductive material and / or a thermally conductive material, and the housing is configured to be thermally conductively connected to a cooling stage of the cryostat. The housing may comprise a metal. In this case, the housing comprises or consists, for example, of at least one of the following metals: copper, aluminum, bronze, nickel.

[0044] The electrically conductive material has, for example, an electrical conductivity of at least 10 2 / (Ohm m) and a maximum of 10 12 / (Ohm m). Furthermore, the thermally conductive material has, for example, a thermal conductivity of at least 0.1 W / (m K) and at most 10 5 W / (m K).

[0045] According to at least one embodiment of the electronic device, the variable capacitor is spaced from the housing by first spacers. The variable capacitor, in particular the carrier, is spaced from at least one of the covers by the first spacers. The first spacers are, for example, part of the top cover and / or the bottom cover.

[0046] According to at least one embodiment of the electronic device, the inductor is spaced from the housing by second spacers. In particular, the dielectric substrate is spaced from at least one of the covers. The second spacers are, for example, part of the top cover and / or the bottom cover.

[0047] Each spacer is formed as a rod structure, wherein the rod structures are spaced apart from each other, for example, in lateral directions. In particular, the rod structures extend in the vertical direction. The spacers are formed, for example, integrally with the housing, i.e., the spacers are formed integrally with the housing. Alternatively, the spacers are provided on the top cover and / or on the bottom cover.

[0048] Furthermore, a quantum computer system is specified, wherein the quantum computer system comprises an electronic device as described above. This means that the features relating to the quantum computer system also apply to the electronic device, and vice versa.

[0049] According to at least one embodiment, the quantum computer system comprises an alternating voltage source for generating a voltage oscillating at a frequency in the radio frequency range.

[0050] According to at least one embodiment, the quantum computer system comprises a cryostat with at least one cooling stage. The cooling stage is configured to provide the cryogenic environment.

[0051] According to at least one embodiment, the quantum computer system comprises an electronic device as described above, which is arranged in the cryostat and thermally connected to the cooling stage. For example, a cold finger of the cryostat, in particular of the cooling stage, is thermally connected directly to the housing.

[0052] According to at least one embodiment, the quantum computer system comprises an ion trap arranged in the cryostat and thermally connected to the cooling stage. The ion trap is, in particular, a radiofrequency ion trap, also called a Paul trap, in which an alternating voltage oscillating at radio frequencies is used to trap ions in spatial dimensions. To provide the required voltages, which are usually too high to drive the ion trap directly via a radiofrequency amplifier, the alternating voltage source is connected to the ion trap via the electronic device.

[0053] According to at least one embodiment of the quantum computer system, the AC voltage source is electrically connected to the electronic device via a first signal line.

[0054] According to at least one embodiment of the quantum computer system, the electronic device is electrically connected to the ion trap via a second signal line.

[0055] According to at least one embodiment of the quantum computer system, a type of the first signal line differs from a type of the second signal line.

[0056] In particular, the type of the first signal line is a coaxial cable and the type of the second signal line is a single wire.

[0057] According to at least one embodiment of the quantum computer system, the cryostat has at least two cooling stages, and the electronic device and the ion trap are thermally connected to the same cooling stage. In particular, the at least two cooling stages comprise a first cooling stage and a second cooling stage, wherein the second cooling stage is configured to be at least 10 K or at least 20 K cooler than the first cooling stage. For example, the electronic device and the ion trap are thermally connected to the second cooling stage.

[0058] According to at least one embodiment of the quantum computer system, the cryostat has at least two cooling stages, and the electronic device and the ion trap are thermally connected to different cooling stages. For example, the electronic device is thermally connected to the first cooling stage, and the ion trap is thermally connected to the second cooling stage.

[0059] In the following, the electronic device and the quantum computer system are explained in more detail with reference to embodiments and the associated figures. Fig. 1 shows a schematic view of the electronic device according to an embodiment. The Fig. 2 and Fig. 3 each show a schematic view of the variable capacitor of the electronic device according to an embodiment. Fig. 4 shows a quantum computer system according to an embodiment.

[0060] Elements that are identical or similar, or have the same effect, are provided with the same reference numerals in the figures. The figures and the proportions of the elements depicted in the figures are not to be considered to scale. Rather, individual elements may be exaggerated for clarity and / or clarity.

[0061] The electronic device 1 according to the embodiment of Fig. 1 comprises an inductor 2, a variable capacitor 3, which is electrically connected to the inductor 2, and a housing 10. The inductor 2 and the variable capacitor 3 are completely enclosed by the housing 10. Furthermore, the inductor 2 comprises a superconducting material, in particular a superconducting alloy, and the variable capacitor 3 is designed to change its capacitance. In particular, the inductor 2 and the variable capacitor 3, as well as a capacitive load 15, form a resonant circuit.

[0062] A first input 4, a second input 5, and an output 6 are arranged in the housing 10. The first input 4 is electrically connected to a first node 7, to which the inductor 2 and the variable capacitor 3 are electrically connected. The output 6 is designed to be electrically connected to a capacitive load 15, which is in particular an ion trap. The first input 4 is designed to be connected to an AC voltage source 16, which provides the oscillating circuit with an AC voltage oscillating at radio frequencies. The second input 5 is designed to be connected to a DC voltage source 17, which provides a DC voltage to the variable capacitor 3.

[0063] The variable capacitor 3 according to the embodiment of Fig. 2 is in particular the variable capacitor 3 according to the embodiment of Fig. 1. The variable capacitor 3 comprises a first varactor diode and a second varactor diode, which are electrically connected in series. The anode regions of the varactor diodes 19 face each other, and the cathode regions of the varactor diodes 19 face away from each other. The variable capacitor 3 further comprises a DC voltage source 17, which is connected in parallel with the varactor diodes 19. The variable capacitor 3 further comprises further circuit elements, here three further inductors I and three resistors R, with parts, including one of the further inductors L and one of the resistors R connected in series, being connected in parallel with each other.

[0064] In this embodiment, the varactor diodes 19 are arranged in series between two capacitors C2, which are optional components of the variable capacitor 3.

[0065] The variable capacitor 3 according to the embodiment of Fig. 3 is in particular the variable capacitor 3 according to the embodiment of Fig. 1. The variable capacitor 3 comprises four first capacitors C1 and four electronic switches 20. Each of the electronic switches 20 is connected in series with one of the first capacitors C1, forming a segment. Furthermore, the segments are connected in parallel to each other.

[0066] Capacitance values ​​of the first capacitors C1 may differ from one another. In particular, at least two or all capacitance values ​​of the first capacitors C1 are different from one another. Advantageously, such first capacitors C1 can cover the largest possible tuning range for a given bit depth. For example, the capacitance values ​​for directly adjacent first capacitors C1 double. This means that the capacitance values ​​increase with the power of 2. This means that the variable capacitance can be adjusted with a relative accuracy of 1 / 2^N, where N is the number of implemented electronic switches 20. In the Fig. In the embodiment shown in Figure 3, 1 / 2^4 = 1 / 16, which results in a relative setting accuracy of about 6%.

[0067] In this embodiment, the segments are arranged in series between two capacitors C3, which are optional components of the variable capacitor 3.

[0068] The quantum computer system 21 according to the embodiment of Fig. 4 comprises an electronic device 1 according to Fig. 1, an AC voltage source 16, a DC voltage source 17, an ion trap, and a cryostat 12. The AC voltage source 16 is connected to the first input 4 via a first signal line 8, and the DC voltage source 17 is connected to the second input 5. The output 6 of the electronic device 1 is connected to the ion trap via a second signal line 9. The electronic device 1 and the ion trap are arranged within the cryostat 12.

[0069] The electronic device 1 is thermally connected to a first cooling stage 13 of the cryostat 12 via a cold finger 11, and the ion trap is thermally connected to a second cooling stage 14 of the cryostat 12.

[0070] The invention is not limited to the embodiments described herein. Rather, the invention encompasses any novel feature and any combination of features, including, in particular, any combination of features in the claims, even if this feature or combination itself is not explicitly recited in the claims or embodiments. Information signs 1 electronic device 2 Inductance 3 variable capacitor 4 first entrance 5 second entrance 6 Exit 7 first node 8 first signal line 9 second signal line 10 housings 11 cold fingers 12 Cryostat 13 first cooling stage 14 first cooling stage 15 capacitive load 16 AC voltage source 17 DC voltage source 19 Varactor diode 20 electronic switches 21 Quantum computer system C1..C3 capacitors I additional inductance R resistance

Claims

[1] Electronic device (1) for controlling a capacitive load (15), with - an inductance (2) and - a variable capacitor (3) which is electrically connected to the inductance (2), wherein - the inductance (2) comprises a superconducting material, and - the variable capacitor (3) is designed to change its capacitance. [2] Electronic device (1) according to claim 1, further comprising - a first input (4) which is electrically connected to a first node (7) to which the inductance (2) and the variable capacitor (3) are electrically connected, - a second input (5) which is electrically connected to the variable capacitor (3) in order to provide the variable capacitor (3) with a DC voltage through a DC voltage source (17), and - an output (6) which is electrically connected to the inductance (2), wherein - the first input (4) is designed to be electrically conductively connected to a first signal line (8) which is connected to an AC voltage source (16), and - the output (6) is designed to be electrically conductively connected to a second signal line (9) which is connected to the capacitive load (15). [3] Electronic device (1) according to one of claims 1 or 2, wherein, - the inductance (2) comprises a superconducting alloy comprising at least the superconducting material, and - the superconducting alloy comprises at least two of the elements barium, copper oxide, yttrium, strontium, titanium, magnesium, boron and niobium. [4] Electronic device (1) according to claim 3, wherein the superconducting alloy has a critical temperature of at least 30 K. [5] Electronic device (1) according to one of claims 1 to 4, further comprising - a dielectric substrate, wherein - the inductance (2) is arranged on the dielectric substrate. [6] Electronic device (1) according to claim 5, wherein - the inductance (2) comprises at least one planar wire, and - the flat wire has a spiral shape, or - the inductance (2) comprises at least one wire, and - the wire is wound around a coil body. [7] Electronic device (1) according to one of claims 1 to 6, wherein - the variable capacitor (3) comprises at least two first capacitors (C1) and at least two electronic switches (20), - each of the electronic switches (20) is connected in series with one of the first capacitors (C1) and forms a segment, - the segments are connected parallel to each other. [8] Electronic device (1) according to one of claims 1 to 6, wherein - the variable capacitor (3) comprises at least one varactor diode (19) and a DC voltage source (17), and - the DC voltage source (17) is connected in parallel to the varactor diodes (19). [9] Electronic device (1) according to one of claims 1 to 8, further comprising - a housing (10), wherein - the inductance (2) and the variable capacitor (3) are surrounded by the housing (10). [10] Electronic device (1) according to claim 9, wherein - the housing (10) comprises an electrically conductive material and / or a thermally conductive material, and - the housing (10) is designed to be thermally conductively connected to a cooling stage of the cryostat (12). [11] Electronic device (1) according to one of claims 9 or 10, wherein - the variable capacitor (3) is spaced from the housing (10) by first spacers, and / or - the inductance (2) is spaced from the housing (10) by second spacers. [12] Quantum computer system (21), comprising - an alternating voltage source (16) for generating a voltage oscillating at a frequency in a radio frequency range, - a cryostat (12) with at least one cooling stage (13, 14), - an electronic device (1) according to one of claims 1 to 8, which is arranged in the cryostat (12) and is thermally connected to the cooling stage (13, 14), and - an ion trap arranged in the cryostat (12) and thermally connected to the cooling stage (13, 14), wherein - the AC voltage source (16) is electrically connected to the electronic device (1) via a first signal line (8), and - the electronic device (1) is electrically connected to the ion trap via a second signal line (9). [13] Quantum computer system (21) according to claim 12, wherein - a type of the first signal line (8) is different from a type of the second signal line (9). [14] Quantum computer system (21) according to one of claims 12 or 13, wherein - the cryostat (12) has at least two cooling stages (13, 14), and - the electronic device (1) and the ion trap are thermally connected to the same cooling stage (13, 14). [15] Quantum computer system (21) according to one of claims 12 or 13, wherein - the cryostat (12) has at least two cooling stages (13, 14), and - the electronic device (1) and the ion trap are thermally connected to different cooling stages (13, 14).

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