Low temperature filter module for scalable quantum computing architecture

Abstract

One or more systems, devices, and / or methods of use provided herein relate to signal filters for scalable quantum computing architectures. According to one embodiment, an apparatus may include a circuit board including a plurality of layers, where each of the plurality of layers includes a different absorbing material, and a plurality of signal lines passing through the circuit board, where a first layer of the circuit board includes a first material, and a second layer of the circuit board includes a second material. The first material filters a first signal line traversing at least a first layer of the plurality of layers.

Description

Background Art

[0001] The subject disclosure relates to signal filters and, more particularly, to cryogenic filter modules for scalable quantum computing architectures. Summary of the invention

[0002] The following presents an overview to provide a basic understanding of one or more embodiments of the invention. This overview is not intended to identify key or important elements, or to delineate any scope of a particular embodiment or any scope of the claims. Its sole purpose is to present concepts in a simplified form as a prelude to a more detailed description presented later. In one or more embodiments described herein, devices, systems, and apparatuses are described that facilitate the operation, design, and / or manufacture of cryogenic filter modules for scalable quantum computing architectures.

[0003] According to an embodiment, a system may include an apparatus, wherein the apparatus may include a circuit board and a plurality of signal lines passing through the circuit board, the circuit board including a plurality of layers, wherein each of the plurality of layers includes a different absorptive material, wherein a first layer of the circuit board includes a first material that filters a first signal line passing through at least the first layer of the plurality of layers. An advantage of such an apparatus is that the plurality of layers may act as a low pass filter at a frequency where a reactive component decomposes due to self-resonance.

[0004] In some embodiments of the above device, the second layer of the circuit board may include a second material that filters the first signal line passing through at least the first and second layers of the plurality of layers. An advantage of such a device is that the absorbing materials of the plurality of layers may be selected based on the expected filtering of the first transmission line.

[0005] According to an embodiment, a system may include an apparatus, wherein the apparatus may include a circuit board and a plurality of signal lines passing through the circuit board, the circuit board including a plurality of layers, wherein each of the plurality of layers includes one or more different absorbing materials, wherein a first layer of the circuit board includes a first material and a second material, wherein a first signal line passes through at least the first layer, and wherein the first signal line includes a first width passing through the first material and a second width passing through the second material. An advantage of such a system is that the first material and the second material can be used as a low pass filter for the signal line.

[0006] In some embodiments of the above system, the system may further include a fabricated chip coupled to the first signal line. An advantage of such a system is that the fabricated chip is capable of performing additional filtering and / or attenuation.

[0007] According to an embodiment, a method may include transmitting a signal, and filtering the signal using a filter circuit board, wherein the filter circuit board includes a plurality of layers and a signal line, wherein each of the plurality of layers includes a different absorbing material, the signal line passes through at least a first layer of the plurality of layers, wherein the signal line carries the signal, and wherein the first layer includes a first material that filters the signal line. An advantage of this method is that the plurality of layers enables low pass filtering at a frequency where the reactive component decomposes due to self-resonance.

[0008] In some embodiments, the above method may further include attenuating the signal using an attenuator coupled to the filter circuit board. The advantage of this method is that it can improve the coherence of the signal.

[0009] According to an embodiment, a system may include a device, wherein the device includes a circuit board and a plurality of signal lines passing through the circuit board, the circuit board including a non-absorbing layer and a plurality of absorbing layers, wherein various absorbing layers in the plurality of absorbing layers include different absorbing materials, wherein a first layer of the circuit board includes a first material that filters a first signal line passing through at least a first layer of the plurality of absorbing layers. An advantage of such a device is that the plurality of absorbing layers can act as a low pass filter at a frequency where the reactance component decomposes due to self-resonance.

[0010] According to an embodiment, a method may include determining a desired frequency response of a filter, selecting one or more absorbing materials based on the desired frequency response, selecting one or more signal line traversal lengths for the one or more absorbing materials, and assembling a circuit board including a plurality of layers, wherein each of the plurality of layers includes a different absorbing material of the one or more absorbing materials selected based on the desired frequency response. An advantage of this method is that the filter can be designed to provide the desired filter response.

[0011] Various additional details of the various embodiments described herein are presented in the following clauses.

[0012] Clause 1: A system comprising: an apparatus comprising: a circuit board comprising a plurality of layers, wherein each of the plurality of layers comprises a different absorptive material; and a plurality of signal lines passing through the circuit board, wherein a first layer of the circuit board comprises a first material, the first material being configured to filter a first signal line passing through at least a first layer of the plurality of layers. An advantage of such an apparatus is that the plurality of layers can act as a low pass filter at a frequency where a reactive component decomposes due to self-resonance.

[0013] Clause 2: The system of any preceding clause as specified in the Summary, wherein the second layer of the circuit board comprises a second material configured to filter a first signal line passing through at least a first layer and a second layer of the plurality of layers.

[0014] Clause 3: The system of any preceding clause as specified in the Summary, wherein the first signal line comprises a first length through the first layer and a second length through the second layer.

[0015] Clause 4: The system of any preceding clause as specified in the Summary, further comprising one or more fabrication chips bonded to the circuit board.

[0016] Clause 5: The system of any preceding clause as specified in the Summary, wherein the one or more fabrication chips include at least one of an attenuator or a reactive low pass filter.

[0017] Clause 6: The system of any preceding clause as specified in the Summary, wherein at least one layer of the plurality of layers comprises at least one of an attenuator or a reactive low pass filter.

[0018] Clause 7: A system as described in any preceding clause specified in the Overview, wherein the first layer is formed of an absorbent material, wherein the absorbent material is configured to provide a low pass filter function, and wherein the second layer is formed of a second absorbent material, wherein the second absorbent material is configured to provide a second low pass filter function.

[0019] Clause 8: The system of any preceding clause as specified in the Summary, wherein the type of the first signal line is one of microstrip or stripline.

[0020] Clause 9: A system as described in any preceding clause as specified in the Summary, further comprising a quantum computing system, the quantum computing system comprising the device.

[0021] Clause 10: A system comprising: an apparatus comprising: a circuit board comprising a plurality of layers, wherein each of the plurality of layers comprises one or more different absorptive materials; and a plurality of signal lines passing through the circuit board, wherein a first layer of the circuit board comprises a first material and a second material, wherein a first signal line passes through at least the first layer, and wherein the first signal line comprises a first width passing through the first material and a second width passing through the second material. An advantage of this approach is that the filter can be designed to provide a desired filter response.

[0022] Clause 11: The system of any preceding clause as specified in the Summary, further comprising a fabrication chip coupled to the first signal line.

[0023] Clause 12: The system of any preceding clause as specified in the Summary, wherein the fabrication chip includes at least one of an attenuator or a reactive low pass filter.

[0024] Clause 13: The system of any preceding clause as specified in the Summary, wherein the first signal line passes through at least the first layer and the second layer.

[0025] Clause 14: The system of any preceding clause as specified in the Summary, wherein the second layer comprises at least one of an attenuator or a reactive low pass filter.

[0026] Clause 15: The system of any preceding clause as specified in the Summary, further comprising a second fabrication chip coupled to a second signal line, wherein the second signal line passes through at least a third layer of the plurality of layers.

[0027] Clause 16: The system of any preceding clause as specified in the Summary, wherein the second fabrication chip comprises at least one of an attenuator or a reactive low pass filter.

[0028] Item 17: A method comprising: transmitting a signal; and filtering the signal using a filter circuit board, wherein the filter circuit board comprises: a plurality of layers, wherein each of the plurality of layers comprises a different absorbing material; and a signal line, wherein the signal line passes through at least a first layer of the plurality of layers, wherein the signal line is configured to carry the signal, and wherein the first layer comprises a first material configured to filter the signal line.

[0029] Clause 18: The method of any preceding clause as specified in the Summary, wherein the signal line passes through at least a first layer and a second layer of the plurality of layers, wherein the second layer comprises a second material configured to filter the signal line.

[0030] Clause 19: The method of any preceding clause as specified in the Summary, further comprising filtering the signal with a reactive low pass filter coupled to the filter circuit board.

[0031] Clause 20: The method of any preceding clause as specified in the Summary, further comprising attenuating the signal with an attenuator coupled to the filter circuit board.

[0032] Clause 21: The method of any preceding clause as specified in the Summary, wherein the signal comprises a control signal for a qubit in a quantum computer.

[0033] Clause 22: The method of any preceding clause as specified in the Summary, wherein the signal comprises a readout request signal for a qubit in the quantum computer.

[0034] Clause 23: A system comprising: a device comprising: a circuit board comprising a non-absorbing layer and a plurality of absorbing layers, wherein various absorbing layers of the plurality of absorbing layers comprise different absorbing materials; and a plurality of signal lines passing through the circuit board, wherein a first layer of the circuit board comprises a first material, the first material being configured to filter a first signal line passing through at least a first layer of the plurality of absorbing layers.

[0035] Clause 24: A system as recited in any preceding clause specified in the Summary, wherein the second signal line passes through the non-absorbing layer.

[0036] Clause 25: A method comprising: determining a desired frequency response of a filter; selecting one or more absorptive materials based on the desired frequency response; selecting one or more signal line crossing lengths for the one or more absorptive materials; and assembling a circuit board comprising a plurality of layers, wherein each of the plurality of layers comprises a different absorptive material of the one or more absorptive materials selected based on the desired frequency response. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawing(s) will be provided by the Office upon request and payment of the necessary fee.

[0038] Figure 1 A schematic diagram of an example non-limiting filter module is shown according to one or more embodiments described herein.

[0039] Figure 2 A cross-sectional schematic diagram of an example non-limiting filter module having a fast flux transmission line according to one or more embodiments described herein is shown.

[0040] Figure 3 A second cross-sectional schematic diagram of an example non-limiting filter module having radio frequency control lines according to one or more embodiments described herein is shown.

[0041] Figure 4 A third cross-sectional schematic diagram of an example non-limiting filter module with readout lines according to one or more embodiments described herein is shown.

[0042] Figure 5 Illustrated is a graph comparing absorption characteristics of various absorbing materials having filter functionality according to one or more embodiments described herein.

[0043] Figure 6 An algorithm for designing multiple absorber layers according to one or more embodiments described herein is shown.

[0044] Fig. 7A and 7B Shown is a graph representing filtering of one or more filter modules according to one or more embodiments described herein.

[0045] Fig. 8A A top view of a tapered signal line in a filter module is shown according to one or more embodiments described herein.

[0046] Figure 8B An alternative view of a tapered signal line in a filter module is shown according to one or more embodiments described herein.

[0047] Fig. 9 A schematic diagram of a non-limiting filter module is shown according to one or more embodiments described herein.

[0048] Fig.10 Shown is a graph representing filtering of two filter modules according to one or more embodiments described herein.

[0049] Fig.11 A flow chart of an example non-limiting method for designing a filter module according to one or more embodiments described herein is shown.

[0050] Fig.12 A flow chart illustrating an example non-limiting method of filtering an electromagnetic signal according to one or more embodiments described herein.

[0051] Fig.13 A flow chart illustrating an example non-limiting method of filtering an electromagnetic signal according to one or more embodiments described herein.

[0052] Fig.14 A flow chart of an example non-limiting method for designing a filter module according to one or more embodiments described herein is shown. DETAILED DESCRIPTION

[0053] The following detailed description is merely illustrative and is not intended to limit the application or use of the embodiments and / or the embodiments. In addition, it is not intended to be bound by any explicit or implicit information presented in the foregoing background technology or summary or detailed description.

[0054] Quantum computing is generally the use of quantum mechanical phenomena to perform computational and information processing functions. Quantum computing can be viewed as a contrast to classical computing, which generally utilizes transistors to operate on binary values. That is, while classical computers can operate on bit values ​​of either 0 or 1, quantum computers operate on quantum bits (qubits) that are superpositions of both 0 and 1, which can entangle multiple qubits and can use interference. This quantum superposition allows quantum systems to store and represent large data sets that are difficult to represent classically. Quantum computing has the potential to solve problems that are either impossible to solve or can only be solved slowly on classical computers due to their computational complexity. In many forms of quantum computers, the qubits within the quantum computer are operated by using radio frequency waves. In this way, the quantum computer can receive instructions from classical inputs and then execute the instructions by using waveforms to operate the qubits within the quantum computer.

[0055] Scalable quantum computing architectures require high-density signal delivery for different types of waveform signals. For example, qubits and readout pulses on input, fast flux pulses on input, and readout pulses on output have different unique filtering and thermalization requirements in order to optimize qubit performance. Therefore, filters for different types of signals require specific frequencies and roll-offs to minimize signal degradation, especially in baseband applications. Designing filters with desired roll-offs and cut-off frequencies is challenging for absorbing materials, which have their own characteristic roll-offs. Therefore, the disclosed subject matter can adopt various techniques to implement a modular architecture for passively filtering noise, attenuating noise, and thermalizing signals as signals pass between temperatures.

[0056] In view of the above-mentioned problems related to filtering of signals used for the operation of a quantum computer, the present disclosure can be implemented to produce solutions to these problems in the form of devices, systems, apparatuses and / or methods, which may include: a circuit board including multiple layers, wherein each of the multiple layers includes a different absorbing material, and multiple signal lines passing through the circuit board, wherein a first layer of the circuit board includes a first material that filters a first signal line passing through at least the first layer of the multiple layers. An advantage of such a device, system, apparatus and / or method is that the multiple layers can be used as a low-pass filter at a frequency where the reactance component is decomposed due to self-resonance. For example, each of the multiple absorbing layers through which the signal line passes can contribute to the filtering of the signal line, thereby achieving the desired filtering of the signal line.

[0057] One or more embodiments are now described with reference to the accompanying drawings, wherein the same reference numerals are used to refer to the same elements throughout. In the following description, for the purpose of explanation, many specific details are set forth in order to provide a more thorough understanding of one or more embodiments. However, it is apparent that in various cases, one or more embodiments may be practiced without these specific details.

[0058] In addition, it should be understood that the embodiments depicted in one or more of the figures described herein are for illustration only and, therefore, the architecture of the embodiments is not limited to the systems, devices and / or components depicted therein, nor is it limited to any specific order, connection and / or connection of the systems, devices and / or components depicted therein.

[0059] Now turning to the attached figure, Figure 1 A schematic diagram of an example non-limiting filter thermalization module 100 is shown, in accordance with one or more embodiments described herein.

[0060] As shown, the filter thermalization module 100 may include a connector 102 (e.g., an ardent), a filter chip 104, an absorption filter 140, and a second connector 106. In one embodiment, the connector 102 may bring a signal to the filter thermalization module 100. The signal may then pass through the filter chip 104. In one embodiment, the filter chip 104 may include a resonant filter 110, a passive filter 120, and an attenuator 130. In another embodiment, the filter chip 104 may additionally include a reactive low-pass filter. The signal may then pass from the filter chip 104 through the absorption filter 140, and the second connector 106 may allow the filtered and attenuated signal to leave the board.

[0061] Figure 2A cross-sectional schematic diagram of an example non-limiting filter module 200 having a fast flux transmission line (e.g., a Z-controlled transmission line) according to one or more embodiments described herein is shown. As shown, the filter module 200 may include a first connector 201, a second connector 202, a chip shield 203, a filter chip 205, a ball grid 206, an interposer 207, a bump bond 208, a signal line 250, an absorption layer 240, an absorption layer 230, an absorption layer 220, an absorption layer 210, and a non-absorption layer 260. In an embodiment, the absorption layers 210-240 may include an absorption material that filters out high frequency radiation. In an embodiment, the absorption material may include a material such as a black body absorber. In one or more embodiments, absorption materials that provide different amounts of filtering and roll-off may be selected. Therefore, different forms of absorption materials may be selected depending on the required filtering and roll-off. For example, layer 240 may include a first type of absorption material, layer 230 may include a second type of absorption material, layer 220 may include a third type of absorption material, and layer 210 may include a fourth type of absorption material. In one embodiment, lossy (e.g., dissipating electrical energy) and / or magnetically loaded (e.g., magnetic absorbent) absorbent materials may be used. In one embodiment, layers 210-240 may be layered according to increased absorption in descending layers. For example, layer 240 may be more absorbent than layer 230, and layer 230 may be more absorbent than layer 220. In other embodiments, layers 210-240 may be layered according to decreased absorption in descending layers. For example, layer 240 may be less absorbent than layer 230, and layer 230 may be less absorbent than layer 220. In one embodiment, the absorbent material may include materials such as polyurethane foam, silicone rubber, carbon, or materials formed by a lamination manufacturing process. In one embodiment, the absorbent material may include one or more forms of Eccosorb®. In one embodiment, signal line 250 may pass through one or more of layers 210-240 based on the required filtering of signal line 250. For example, as shown, signal line 250 passes horizontally through layers 240 and layer 230, but not through layers 210 or 220. Thus, signal line 250 is filtered by layers 240 and 230, but not by layers 220 and 210. It should be understood that signal line 250 can pass through different layers at different lengths. For example, as shown, the length of signal line 250 passing through layer 240 is greater than the length passing through layer 230. When the length of the layer through which signal line 250 passes affects the filtering of signal line 250, different traversal lengths can be selected to achieve different amounts of filtering and roll-off. It should be understood that signal line 250 can include any form of microwave or RF signal medium, such as but not limited to microstrip or stripline. It should also be understood that layers within the plurality of layers can include additional elements other than absorbent materials. For example, one or more of the plurality of layers can include elements such as attenuators or reactive low-pass filters.

[0062] Figure 3 A second cross-sectional schematic diagram of an example non-limiting filter module 200 having a radio frequency control line (e.g., an XY control transmission line) according to one or more embodiments described herein is shown. For the sake of brevity, repeated descriptions of similar elements and / or processes employed in corresponding embodiments are omitted. In one embodiment, the filter module 200 may include multiple signal lines. For example, Figure 3 As shown, filter module 200 may include second signal line 350. As shown, second signal line 350 horizontally passes through layer 220, but not through layer 210, layer 230, or layer 240. Therefore, signal line 350 is filtered by layer 220, but not by layer 210, layer 230, or layer 240.

[0063] Figure 4 A third cross-sectional schematic diagram of an example non-limiting filter module 200 with a readout line according to one or more embodiments described herein is shown. For the sake of brevity, repeated descriptions of similar elements and / or processes employed in the corresponding embodiments are omitted. In one embodiment, the filter module 200 may additionally include a third signal line 450, which is a readout line intended to read out the state of one or more qubits in a quantum computer. Since the readout line does not typically utilize filtering, the third signal line 450 does not pass through the filter chip, and does not pass through any of the layers 210, 220, 230, or 240. Instead, the signal line 450 as shown passes through the non-absorbing layer 260, which does not provide any filtering to the third signal line 450. It should be understood that in one embodiment, the filter thermalization module described herein may include any number of absorbing layers and / or any number of signal lines. In another embodiment, the signal line may pass through any number of absorbing layers. For example, a fourth signal line (not shown) may pass through any combination of layers 210, 220, 230, and 240 or layers. It should also be understood that signal lines may pass through any layer to any distance or length.

[0064] In an embodiment, various forms and / or types of absorbing materials may be utilized. For example, different absorbing materials may have different properties, such as magnetic permeability (e.g., the change in the magnetic field within the material), magnetic loss tangent (e.g., the amount of magnetic power lost in the material compared to the amount of magnetic power stored in the material), dielectric loss tangent (e.g., a measure of the dissipation of electrical energy through the material), attenuation per unit length (e.g., the amount of attenuation provided by a specific length of the material), and other properties. Thus, different absorbing materials or types of absorbing materials may provide different filtering functions. In an embodiment, absorbing materials having a magnetic permeability in the range of 1.1-4.5 for a 1 GHz signal may be utilized. In an embodiment, absorbing materials having a magnetic loss tangent in the range of 0-0.8 for a 1 GHz signal may be utilized. In an embodiment, absorbing materials having a dielectric loss tangent in the range of 0.04-0.07 for a 1 GHz signal may be utilized. In an embodiment, absorbing materials having an attenuation per unit length in the range of 0.09 dB to 27 dB per centimeter may be used. It should be understood that the absorbing material can have different properties, depending on the frequency of the signal passing through the absorbing material. For example, the material can have different attenuation values ​​per unit length for 1 GHz and 2 GHz signals, respectively. In one embodiment, the filter can include a first absorbing material having a magnetic permeability of 1.4 for a 1 GHz signal, a magnetic loss tangent of 0.02 for a 1 GHz signal, a dielectric loss tangent of 0.04 for a 1 GHz signal, and an attenuation per unit length of 0.16 dB per centimeter. The filter can also include a second absorbing material having a magnetic permeability of 4.1 for a 1 GHz signal, a magnetic loss tangent of 0.20 for a 1 GHz signal, a dielectric loss tangent of 0.09 for a 1 GHz signal, and an attenuation per unit length of 2.8 dB per centimeter.

[0065] Figure 5 A graph 500 comparing the absorption characteristics of various absorption material types with a Bessel-Thompson filter according to one or more embodiments described herein is shown. For the sake of brevity, repeated descriptions of similar elements and / or processes employed in corresponding embodiments are omitted.

[0066] The y-axis of graph 500 shows absorption (measured in dB) and the x-axis represents the frequency of the signal (measured in Hz). Thus, graph 500 shows absorption plotted as a function of frequency for a signal line passing through 1 cm through different types of absorbing materials. Line 510, shown as solid blue, represents a first absorbing material and line 520, shown as solid orange, represents a second absorbing material type. Line 530, shown as solid green, represents a third absorbing material type. Line 540, shown as solid red, represents a fourth absorbing material. Line 525, shown as dashed orange, represents the Bessel Thompson filter f -3dB = 2 GHz. The dashed green line 535 represents the Bessel Thompson filter f -3dB = 1 GHz. The line 545 shown as a dashed red line represents the Bessel Thompson filter f -3dB = 200 MHz. As shown, in some cases, a single type of absorbing material by itself may not provide the desired amount of filtering, as shown by the difference between the solid and dashed lines. Therefore, as described in more detail below, multiple types of absorbing materials and / or different traversal lengths may be utilized in order to achieve the desired amount of filtering.

[0067] Figure 6 An algorithm 600 for designing multiple absorber layers according to one or more embodiments described herein is shown. For the sake of brevity, repeated descriptions of similar elements and / or processes employed in corresponding embodiments are omitted.

[0068] As shown, 610 represents a column vector of a matrix showing absorption versus frequency data for various absorbing materials having different absorption characteristics, e.g. Figure 5 620 represents the different lengths through the different absorbent materials represented in column 610. 630 is a column vector representing the filter transfer function of the signal line (e.g., absorption versus frequency). Since the absorption at many more frequency points is known than the type of absorbent material, a least squares optimization can be used. For example, column 610 can be represented as the variable , column 620 can be represented as a variable And column 630 can be represented as a variable ,in Therefore, the vector represents how much of each different type of absorbing material should be used to assemble a filter with the desired response. Therefore, by finding the solution , which minimizes , therefore, a filter can be designed that provides the desired filter response.

[0069] Fig. 7A and7B Graphs 700 and 750 are shown, respectively, illustrating filtering of one or more filter modules according to one or more embodiments described herein. For the sake of brevity, repeated descriptions of similar elements and / or processes employed in the corresponding embodiments are omitted.

[0070] The Y-axis of graphs 700 and 750 shows absorption (measured in dB), and the x-axis represents the frequency of the signal (measured in Hz). Thus, graphs 700 and 750 show absorption plotted as a function of frequency for a signal line passing through a filter module designed using least squares optimization as described above with respect to FIG. 7 . Line 710 of graph 700 represents a filter function of a 4th order Bessel Thompson 1.9 GHz cutoff. This filter function can then be used as the described filter function of algorithm 600, as described above with reference to FIG. 7 . Line 720 of graph 700 represents a filter function of a filter designed using least squares optimization, as described above with reference to FIG. 7 , where the filter function of line 710 is the described filter function. The filter function represented by line 720 includes a traversal distance of 2.13 cm for the absorbent material type MF 112 and 0.611 cm for MF 117. As shown, line 720 is very close to line 710, showing the effectiveness of filter modules utilizing multiple absorbent layers and different distances through the absorbent layers.

[0071] Line 770 of graph 750 represents a filter function for a 4th order Bessel Thompson 1 GHz cutoff. This filter function can then be used as the described filter function of algorithm 600, as described above with reference to FIG. 7. Line 770 of graph 750 represents a filter function for a filter designed using least squares optimization, as described above with reference to FIG. 7, where the filter function of line 760 is the described filter function. The filter function represented by line 870 includes a traversal distance of 0.317 cm for absorbent material type MF 124 and 0.6 cm for MF 175. As shown, line 770 is very close to line 760, showing the effectiveness of a filter module utilizing multiple absorbent layers and different distances through the absorbent layers.

[0072] Fig. 8A A top view 800 of a tapered signal line in a filter module 805 is shown according to one or more embodiments described herein.

[0073] In one embodiment, instead of Figure 2-4Instead of stacking multiple layers on top of each other as shown, multiple absorbing materials can be placed adjacent to each other in a single layer. For example, the filter module 805 can include a first absorbing material 810 adjacent to a second absorbing material 820. The signal line 830 can pass through the first absorbing material 810 and the second absorbing material 820. In one embodiment, the length of the first absorbing material 810 and the length of the second absorbing material 820 can be determined using the least squares optimization as described above with reference to FIG. 7. In another embodiment, the width of the signal line 830 can vary between various absorbing materials. For example, as shown, the signal line 830 includes a first width at a point 832 in the first absorbing material 810 and a second width at a point 834 in the second absorbing material 820. As shown, the first width is greater than the second width, but it should be understood that any width difference between any number of absorbing materials and / or any number of width variations can be envisioned. In one embodiment, by gradually reducing the width of the signal line 830, the impedance matching and return loss of the signal 830 can be improved, thereby improving the performance of the quantum computing system associated with the filter module 805.

[0074] Figure 8B An alternative view 815 of a tapered signal line in a filter module 805 according to one or more embodiments described herein is shown. For the sake of brevity, repeated descriptions of similar elements and / or processes employed in corresponding embodiments are omitted.

[0075] As mentioned above Fig. 8A As described above, in one embodiment, rather than stacking the absorbent materials into layers, as described above with reference to Figure 2-4 As described, multiple absorbent materials can be placed adjacent to each other in a single layer. For example, as shown in view 815, a first absorbent material 810 is placed adjacent to a second absorbent material 820 in a single layer. In another embodiment, one of the multiple layers can include one or more absorbent materials. For example, one of the multiple layers can include a first absorbent material and a second absorbent material adjacent to each other.

[0076] Fig. 9 A schematic diagram of a non-limiting filter module 900 according to one or more embodiments described herein is shown. For the sake of brevity, repeated descriptions of similar elements and / or processes employed in corresponding embodiments are omitted.

[0077] The filter module 900 includes a plurality of absorbing layers (e.g., layers 910, 920, and 930) and a signal line 940 passing through layers 930 and 920. In one embodiment, when the signal line 940 passes between different layers, a via can be used to connect portions of the signal line 940. For example, a via 950 connects a portion of the signal line 940 passing through layer 920 to a portion of the signal line 940 passing through layer 910. Similarly, a via 960 connects a portion of the signal line 940 passing through layer 930 to a portion of the signal line 940 passing through layer 920. In one embodiment, different vias can be designed for different portions of the filter module 900 to provide impedance matching between layers. For example, based on different characteristics of the layers connected by the vias, the via 950 can be designed differently from the via 960. In another embodiment, the signal line 940 can include one or more microstrips having different geometries, wherein the microstrips have different geometries and can achieve different filtering characteristics when combined.

[0078] Fig.10 A graph representing filtering of one or more filter modules according to one or more embodiments described herein is shown. For the sake of brevity, repeated descriptions of similar elements and / or processes employed in the corresponding embodiments are omitted.

[0079] The Y-axis of the graph 1000 shows absorption (measured in dB), and the x-axis represents the frequency of the signal (measured in Hz). Thus, the graph 1000 shows the absorption plotted as a function of the frequency of a signal line that passes through a filter module designed using least squares optimization as described above with respect to FIG. 7 , as described above in FIG. Fig. 9 A and 9B and the filter modules designed as described above in Fig.10 . Line 1030 of graph 1000 represents a filter function of a 4th order Bessel Thompson 1.9 GHz cutoff, which is used in the graph as a representation of a desired filter function. Line 1005 represents a filter function of a filter designed using least squares optimization as described above with reference to FIG. 7. Line 1010 represents a filter function of a filter designed using least squares optimization as described above with reference to FIG. Fig. 9 A and 9B. Line 1020 represents the filter function of the filter designed as described in FIG. Fig.10 It should be appreciated that all of lines 1005, 1010, and 1020 approximate line 1030, illustrating the effectiveness of one or more embodiments of the filter module described herein.

[0080] Fig.11 A flow chart of an example non-limiting method for designing a filter module according to one or more embodiments described herein is shown.

[0081] At 1110 , a desired frequency response of a filter (eg, vector b) may be provided.

[0082] At 1120, frequency dependent material properties may be obtained to arrive at an absorption per unit length for a particular transmission line geometry to be used in the filter.

[0083] At 1130, a matrix (eg, A) can be assembled showing the absorption per unit length versus frequency for different absorbing materials considered for use in the filter.

[0084] At 1140, the vector may be solved by using least squares optimization (For example, the solution that minimizes ) to determine the length of different absorbent materials.

[0085] At 1150, a finite element simulation of a filter may be performed where one of the absorbing layers has sections of different lengths. For example, a finite element simulation of a designed filter may be utilized to compare a filter function of the designed filter to a desired filter function.

[0086] Fig.12 A flow chart of an example non-limiting method 1200 of filtering an electromagnetic signal according to one or more embodiments described herein is shown. For the sake of brevity, repeated descriptions of similar elements and / or processes employed in corresponding embodiments are omitted.

[0087] At 1210, method 1200 may include transmitting a signal. For example, as described above with reference to Figure 2-6 As described, the signals may include various signals used for the operation of qubits of a quantum computer, such as fast flux transmission and radio frequency control signals.

[0088] At 1220, method 1200 may include filtering the signal using a filter circuit board, wherein the filter circuit board includes a plurality of layers, wherein each of the plurality of layers includes a different absorbing material, and a signal line that passes through at least a first layer of the plurality of layers, wherein the signal line carries the signal, and wherein the first layer includes a first material that filters the signal line. For example, as described above with reference to Figure 2-4 As described above, the signal line can pass through one or more absorption layers, wherein each absorption layer through which the signal line passes helps to filter the signal carried by the signal line. Therefore, the one or more absorption layers through which the signal line passes can achieve the desired filtering function, which may not be possible in the case of a single absorption layer.

[0089] Fig.13A flow chart of an example non-limiting method 1400 of filtering a signal according to one or more embodiments described herein is shown. For the sake of brevity, repeated descriptions of similar elements and / or processes employed in the corresponding embodiments are omitted.

[0090] At 1310, method 1300 may include transmitting a signal. For example, as described above with reference to Figure 2-6 The signal may include various signals for the operation of the qubits of the quantum computer, such as fast flux transmission and radio frequency control signals. In another embodiment, the electromagnetic signal may include any type of signal related to the operation of the qubit or quantum hardware, such as a qubit control signal, a readout request signal, and / or other operation signals.

[0091] At 1320, method 1300 may include filtering a signal using a filter circuit board, wherein the filter circuit board includes a plurality of layers and a signal line, wherein each of the plurality of layers includes a different absorbing material, the signal line traverses at least a first layer of the plurality of layers, wherein the signal line carries a signal, and wherein the first layer includes a first material that filters the signal line. For example, as described above with reference to Figure 2-4 As described above, the signal line can pass through one or more absorption layers, wherein each absorption layer that the signal line passes through helps to filter the signal carried by the signal line. Therefore, the one or more absorption layers that the signal line passes through can achieve the desired filtering function, which may not be possible in the case of a single absorption layer.

[0092] At 1330, method 1300 may include filtering the signal using a reactive low pass filter coupled to a filter circuit board. Figure 2-4 As described, a fabricated chip including a reactive low pass filter may be coupled to a circuit board. In another example, a circuit board may include a reactive low pass filter between layers in a plurality of layers.

[0093] At 1340, method 1300 may include attenuating the signal using an attenuator coupled to the filter board. Figure 2-4 As described, a fabricated chip including an attenuator may be coupled to a circuit board. In another example, a circuit board may include an attenuator between layers in a plurality of layers.

[0094] At 1350, method 1300 may include receiving a second signal, wherein the second signal includes a readout of a state of a qubit in a quantum computer. Figure 2-4 As described above, the readout signal does not need to be filtered, so the signal line carrying the readout signal can pass through the non-absorption layer of the filter circuit board to prevent filtering of the readout signal.

[0095] Fig.14A flow chart of an example non-limiting method 1400 for designing a filter module according to one or more embodiments described herein is shown.

[0096] At 1410, method 1400 can include determining a desired frequency response. For example, based on the type of signal line, a desired frequency response can be identified or provided.

[0097] At 1420, method 1400 can include selecting one or more absorbing materials based on the desired frequency response. For example, as described in detail above, a least squares optimization method can be utilized to select one or more different absorbing materials to achieve the desired frequency response.

[0098] At 1430, method 1400 may include selecting one or more signal line traversal lengths for one or more absorbing materials. For example, as described above, a least squares optimization method may be utilized to select the signal line traversal lengths through the one or more absorbing materials based on a desired frequency response.

[0099] At 1440 , method 1400 may include assembling a circuit board including a plurality of layers, wherein respective layers of the plurality of layers include a different absorbing material of one or more absorbing materials selected based on a desired frequency response.

[0100] The advantage of such a method, system and / or device is that the filter module produced by such a method, system and / or device implements a specific filtering function at low frequency, where the reactance component is decomposed due to self-resonance. For example, the filter in the quantum computer requires a specific cutoff frequency and roll-off to minimize signal degradation. In this way, the filter module as described above can achieve the desired filtering function by passing the signal line through one or more absorption layers, wherein each layer through which the signal line passes contributes to filtering. In addition, by changing the distance that the signal line passes through the absorption layer, different filtering functions can be achieved. As described above, by utilizing least squares optimization to select various absorption layers and signal lines passing through various absorption layers, the desired filtering function that produces the desired cutoff frequency and roll-off can be achieved. By achieving this desired filtering function, the filter module described herein can reduce signal degradation, thereby improving the performance of the quantum computer by reducing the degradation of microwave and / or radio frequency signals used to manipulate the qubits within the quantum computer.

[0101] In view of one or more embodiments described herein, a practical application of the apparatus described herein is reduced signal degradation in quantum computing systems. This helps improve the performance of quantum computing systems, thereby improving the processing power, speed and / or accuracy of quantum systems.

[0102] In addition, one or more embodiments described herein can be employed in real-world systems based on the disclosed teachings. For example, one or more embodiments described herein can function within a system that can receive a quantum job request as input and can generate real-world physical pulses that operate on one or more qubits of a quantum system. The output signals of one or more physical qubit devices and / or the pulses that operate on one or more qubits can be filtered by a device according to one or more embodiments described herein. In response to performing one or more physical operations on the real-world qubits of a quantum system, the corresponding quantum system can produce one or more quantum results.

[0103] It should also be understood that one or more embodiments described herein may employ hardware to solve problems that are highly technical, not abstract, and cannot be performed as a set of mental actions by a human being. For example, one person or even thousands of people cannot efficiently, accurately, and / or effectively filter signals from a quantum computer.

[0104] One or more embodiments described herein may be fully operable to perform one or more other functions (e.g., fully powered on, fully executed, and / or another function) while also performing one or more operations described herein. It should be understood that such simultaneous multi-operation execution is beyond the capabilities of the human mind.

Claims

1. A system comprising: Equipment, the equipment comprising: a circuit board comprising a plurality of layers, wherein each of the plurality of layers comprises a different absorbent material; and A plurality of signal lines pass through the circuit board, wherein a first layer of the circuit board includes a first material configured to filter a first signal line traversing at least a first layer of the plurality of layers. 2 . The system of claim 1 , wherein the second layer of the circuit board comprises a second material configured to filter a first signal line traversing at least a first layer and a second layer of the plurality of layers. 3 . The system of claim 2 , wherein the first signal line comprises a first length across the first layer and a second length across the second layer.

4. The system of any preceding claim, further comprising one or more fabrication chips bonded to the circuit board.

5. The system of claim 4, wherein one or more fabricated chips include at least one of an attenuator or a reactive low pass filter.

6. The system of any of the preceding claims, wherein at least one layer of the plurality of layers comprises at least one of an attenuator or a reactive low pass filter.

7. The system of claim 2, wherein the first layer is formed of an absorbent material, wherein the absorbent material is configured to provide a low pass filter function, and wherein the second layer is formed of a second absorbent material, wherein the second absorbent material is configured to provide a second low pass filter function.

8. The system according to any one of the preceding claims, wherein the first signal line is of the type one of microstrip or stripline.

9. The system of any preceding claim, wherein one or more of the plurality of layers comprises a non-absorbing material.

10. A system comprising: Equipment, the equipment comprising: A circuit board comprising a plurality of layers, wherein each of the plurality of layers comprises one or more different absorbent materials; and A plurality of signal lines pass through the circuit board, wherein a first layer of the circuit board includes a first material and a second material, wherein a first signal line passes through at least the first layer, and wherein the first signal line includes a first width passing through the first material and a second width passing through the second material.

11. The system according to claim 10, further comprising: A chip is fabricated that is connected to the first signal line.

12. The system of claim 11, wherein the fabricated chip comprises at least one of an attenuator or a reactive low pass filter.

13. The system according to any of the preceding claims 10 to 12, wherein the first signal line traverses at least the first layer and the second layer.

14. The system of claim 13, wherein the second layer comprises at least one of an attenuator or a reactive low pass filter.

15. The system according to any one of the preceding claims 10 to 14, further comprising: A second fabrication chip is coupled to a second signal line, wherein the second signal line traverses at least a third layer of the plurality of layers.

16. The system of claim 15, wherein the second fabricated chip comprises at least one of an attenuator or a reactive low pass filter.

17. A method comprising: Transmitting signals; and The signal is filtered using a filter circuit board, wherein the filter circuit board comprises: a plurality of layers, wherein each layer of the plurality of layers comprises a different absorbent material; and A signal line traverses at least a first layer of the plurality of layers, wherein the signal line is configured to carry the signal, and wherein the first layer includes a first material configured to filter the signal line. 18 . The method of claim 17 , wherein the signal line traverses at least a first layer and a second layer of the plurality of layers, wherein the second layer comprises a second material configured to filter the signal line.

19. The method according to any one of claims 17 to 18, further comprising: The signal is filtered using a reactive low pass filter coupled to the filter circuit board.

20. The method according to any one of claims 17 to 19, further comprising: The signal is attenuated using an attenuator coupled to the filter circuit board.

21. A method according to any one of the preceding claims 17 to 20, wherein the signal comprises a control signal for a qubit in a quantum computer.

22. A method according to any one of the preceding claims 17 to 21, wherein the signal comprises a readout request signal for a qubit in a quantum computer.

23. A system comprising: Equipment, the equipment comprising: A circuit board comprising a non-absorbent layer and a plurality of absorbent layers, wherein each of the plurality of absorbent layers comprises a different absorbent material; and A plurality of signal lines pass through the circuit board, wherein a first layer of the circuit board includes a first material configured to filter a first signal line passing through at least a first layer of the plurality of absorber layers.

24. The system of claim 23, wherein a second signal line passes through the non-absorbing layer.

25. A method comprising: Determine the desired frequency response of the filter; selecting one or more absorbing materials based on the desired frequency response; selecting one or more signal line traversal lengths for the one or more absorbing materials; and A circuit board is assembled including a plurality of layers, wherein respective layers of the plurality of layers include a different absorbing material of one or more absorbing materials selected based on the desired frequency response.

Images