Patent Application
20210068320
The subject disclosure relates to magnetic field and radiation shielding for one or more superconductive devices, and more specifically, to qubit packaging assemblies and/or multi-layer enclosures that can shield one or more superconducting devices from magnetic fields and/or radiation.
The following presents a summary to provide a basic understanding of one or more embodiments of the invention. This summary is not intended to identify key or critical elements, or delineate any scope of the particular embodiments or any scope of the claims. Its sole purpose is to present concepts in a simplified form as a prelude to the more detailed description that is presented later. In one or more embodiments described herein, apparatuses and/or methods that can shield superconducting devices from magnetic fields and/or radiation are described.
According to an embodiment, an apparatus is provided. The apparatus can comprise a multi-layer enclosure that can shield a superconducting device from a magnetic field and radiation. The multi-layer enclosure can comprise a superconducting material layer that can have a thickness that inhibits a penetration of the multi-layer enclosure by the magnetic field. The multi-layer enclosure can further comprise a metal layer adjacent to the superconducting material layer. The metal layer can have a high thermal conductivity that achieves thermalization with the superconducting material layer. The multi-layer enclosure can also comprise a radiation shield layer adjacent to the superconducting material.
According to an embodiment, an apparatus is provided. The apparatus can comprise a qubit packaging assembly having a circuit board positioned between a first metal cover and a second metal cover. The circuit board can house a quantum processor, and a surface of the second metal cover facing the circuit board can comprise a groove that houses an indium seal.
According to an embodiment, a method is provided. The method can comprise electroplating a metal enclosure with a superconducting material to form a magnetic field shield. The method can also comprise depositing a radiation shield onto the superconducting material. The metal enclosure, superconducting material, and radiation shield can form a multi-layer enclosure that shields a superconducting device from a magnetic field and radiation.
The following detailed description is merely illustrative and is not intended to limit embodiments and/or application or uses of embodiments. Furthermore, there is no intention to be bound by any expressed or implied information presented in the preceding Background or Summary sections, or in the Detailed Description section.
One or more embodiments are now described with reference to the drawings, wherein like referenced numerals are used to refer to like elements throughout. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a more thorough understanding of the one or more embodiments. It is evident, however, in various cases, that the one or more embodiments can be practiced without these specific details. Additionally, features depicted in the drawings with like shading, cross-hatching, and/or coloring can comprise shared compositions and/or materials.
Radiation can decrease the performance of various superconducting devices, such as superconducting qubits and/or microwave resonators. For example, radiation can impair the tunability, fixed frequency of superconducting qubits, and/or qubit lifetime. Possible sources of radiation can include, for example: stray light, cosmic rays, background radioactivity, slow heat release of various defect, and/or thermal radiation. Radiation can generate thermal quasiparticles, thereby reducing cavity resonator quality factor and impacting the coherence of the superconducting qubits as well as reducing qubit fidelities. Additionally, magnetic fields are known to reduce the performance of both qubits and various types of resonators. For instance, superconducting circuits are cooled in a very low magnetic field in order to minimize the number of trapped vortices.
Various embodiments described herein can regard apparatuses and/or methods for shielding one or more superconducting devices from magnetic fields and/or multiple sources of stray radiation. One or more embodiments, for example, can regard one or more multi-layer enclosures that can shield against magnetic fields and/or radiation while facilitating various thermal conditions (e.g., facilitating rapid cooling of the enclosure and/or the one or more superconducting devices). Additionally, one or more embodiments can include one or more qubit assembly packages that can facilitate shielding one or more superconducting quit processors. Further, various embodiments described herein can comprise one or more manufacturing methods regarding the multi-layer enclosures and/or qubit packaging assemblies.
In one or more embodiments, the one or more metal layers 102 can be free of magnetic impurities. For example, the one or more metal layers 102 can be annealed in various gases (e.g., low pressure oxygen gas or a vacuum) to eliminate impurities and/or oxygen vacancies. Further, the one or more metal layers 102 can have a high thermal conductivity so as to facilitate thermalization between the various layers of the multi-layer enclosure 100 (e.g., achieving thermalization with the one or more superconducting material layers 104). Example materials that can be comprised within the one or more metal layers 102 can include, but are not limited to: oxygen-free high thermal conductivity (“OFHC”) copper, electrolytic tough pitch (“ETP”) copper, gold, silver, a combination thereof, and/or the like. One of ordinary skill in the art will recognize that a thickness of the one or more metal layers 102 can vary depending on the size and/or function of the multi-layer enclosure 100. For instance, an exemplary thickness range for the one or more metal layers 102 can be greater than or equal to 2 millimeters (mm) and less than or equal to 1 centimeter (cm). Further, the thickness of the one or more metal layers 102 can be uniform throughout the multi-layer enclosure 100 (e.g., as shown in
In one or more embodiments, the one or more superconducting material layers 104 can comprise one or more materials that can exhibit superconducting properties, such as little to no electrical resistance and/or expulsion of magnetic flux. Example materials that can comprise the one or more superconducting material layers 104 can include, but are not limited to: indium, rhenium, yttrium barium copper oxide, tin (Sn), aluminum (Al), titanium nitride (TiN), a combination thereof, and/or the like. In various embodiments, the one or more superconducting material layers 104 can have a thickness higher than the penetration depth of one or more magnetic fields. One of ordinary skill in the art will recognize that a thickness of the one or more superconducting material layers 104 can vary depending on the size and/or function of the multi-layer enclosure 100. For instance, an exemplary thickness range for the one or more superconducting material layers 104 can be greater than or equal to 200 microns and less than or equal to 1 mm. Further, the thickness of the one or more superconducting material layers 104 can be uniform throughout the multi-layer enclosure 100 (e.g., as shown in
In one or more embodiments, the one or more radiation shield layers 106 can comprise materials that can reflect and/or refract ionizing radiation and/or infrared (“IR”) radiation. Example materials that can comprise the one or more radiation shield layers 106 can include, but are not limited to: AEROGLAZE® Z306 coating, and/or the like. One of ordinary skill in the art will recognize that a thickness of the one or more radiation shield layers 106 can vary depending on the size and/or function of the multi-layer enclosure 100. For instance, an exemplary thickness range for the one or more radiation shield layers 106 can be 1 mm or thicker. Further, the thickness of the one or more radiation shield layers 106 can be uniform throughout the multi-layer enclosure 100 (e.g., as shown in
As shown in
For example, the one or more superconducting material layers 104 can serve as a magnetic field shield by inhibiting one or more magnetic fields from penetrating the multi-layer enclosure 100 and interacting with the one or more superconducting devices. Also, the one or more radiation shield layers 106 can serve as a radiation shield by inhibiting radiation (e.g., IR radiation) from penetrating the multi-layer enclosure 100 and interacting with the one or more superconducting devices. Further, the one or more metal layers 102 can provide high thermal conductivity to the multi-layer enclosure 100 to facilitate rapid thermal changes in the condition of the multi-layer enclosure 100. For example, the one or more metal layers 102 can comprise OFHC copper that can facilitate in cooling the multi-layer enclosure 100 to temperatures conducive to operation of the one or more superconducting devices.
In various embodiments, the multi-layer enclosure 100 can further comprise one or more doors to facilitate access to the inside cavity of the multi-layer enclosure 100. For example, the one or more doors can comprise the same multi-layer structure as the body of the multi-layer enclosure 100 (e.g., as depicted in
In one or more embodiments, the one or more cryogenic magnetic shielding layers 202 can comprise one or more materials that can be highly permeable and/or provide electromagnetic interference (“EMI”) shielding in near absolute zero environment. Example materials that can comprise the cryogenic magnetic shielding layers 202 can include, but are not limited to, murinite, and/or the like. For instance, the cryogenic magnetic shielding layers 202 can comprise cryoperm. One of ordinary skill in the art will recognize that a thickness of the one or more cryogenic magnetic shielding layers 202 can vary depending on the size and/or function of the multi-layer enclosure 100. For instance, an exemplary thickness range for the one or more one or more cryogenic magnetic shielding layers 202 can be greater than or equal to 100 microns and less than or equal to 1 mm. Further, the thickness of the one or more cryogenic magnetic shielding layers 202 can be uniform throughout the multi-layer enclosure 100 (e.g., as shown in
In various examples, the one or more cryogenic magnetic shielding layers 202 can be wrapped light-tight around the one or more radiation shield layers 106. Additionally, multiple sheets of the one or more cryogenic magnetic shielding layers 202 can be welded together to achieve a desired thickness. The one or more cryogenic magnetic shielding layers 202 can further increase the multi-layer enclosure's 100 capacity to shield against magnetic fields. For instance, the one or more cryogenic magnetic shielding layers 202 can provide magnetic field shielding from room temperature environments.
In one or more embodiments, the one or more superinsulation layers 204 comprise one or more superinsulators (e.g., one or more materials that can exhibit near-infinite electrical resistance). Example materials that can comprise the one or more superinsulation layers 204 can include, but are not limited to: aluminized mylar film (e.g., having an exemplary thickness of 125 microns), aluminum foil (e.g., high purity foil with low emissivity qualities that enable superinsulation below 77 degrees Kalvin and/or having an exemplary nominal thickness of 0.08 mm), a superinsulated film with a vacuum deposited aluminum layer deposited on one or two sides of the film to approximately 400 angstrom to provide an effective radiation barrier, a combination thereof, and/or the like. One of ordinary skill in the art will recognize that a thickness of the one or more superinsulation layers 204 can vary depending on the size and/or function of the multi-layer enclosure 100. Further, the thickness of the one or more superinsulation layers 204 can be uniform throughout the multi-layer enclosure 100 (e.g., as shown in
For example, in one or more embodiments an outer surface and an inner surface of a metal layer 102 can be electroplated with superconducting material layers 104; thereby forming a structure in which the metal layer 102 is positioned between two superconducting material layers 104. Further, a radiation shield layer 106 can be positioned adjacent to each of the superconducting material layers 104 such that the metal layer 102 and two superconducting material layers 104 can be located between two radiation shield layers 106 (e.g., as shown in
The one or more silicon chips 402 can be positioned on one or more circuit boards 404 (e.g., printed circuit boards). Further, the one or more circuit boards 404 can be positioned between a first metal cover 406 and a second metal cover 408 (e.g., as shown in
In one or more embodiments, the second metal cover 408 can comprise one or more grooves in a surface of the second metal cover 408 that faces the one or more circuit boards 404. Further, one or more indium seals 410 can be positioned within the one or more grooves. The one or more indium seals 410 can enable an interface between the second metal cover 408 and the one or more circuit boards 404 without compromising the structural integrity of the one or more circuit boards 404. In various embodiments, the second metal cover 408 can be braided to thermalize the second metal cover 408 due to indium becoming superconducting at low temperatures. Also, in one or more embodiments, the first metal cover 406 can be coupled to one or more metal mounting bracket 412. In various embodiments, the one or more metal mounting brackets 412 can be annealed in various gases (e.g., low pressure oxygen) to eliminate impurities and/or oxygen vacancies. Further, the metal mounting bracket 412 can have a high thermal conductivity. Example materials that can comprise the one or more metal mounting brackets 412 can include, but are not limited to: OFHC copper, ETP copper, gold, silver, a combination thereof, and/or the like.
Further, in one or more embodiments the one or more circuit boards 404 can be operably coupled to one or more coaxial cables 414 that can establish an electrical connection with the one or more quantum processors. Additionally, one or more impedance-matched low-pass filters 416 can be operably coupled to the one or more coaxial cables 414. For instance, the one or more one or more impedance-matched low-pass filters 416 can be eccosorb filters.
In various embodiments, the one or more impedance-matched low-pass filters 416, first metal cover 406, second metal cover 408, one or more silicon chips 402, one or more circuit boards 404, and/or indium seals 410 can be substantially surrounded by the one or more multi-layer enclosures 100. As shown in
As shown in
For example, the one or more metal layers 102 can be cleaned (e.g., using acetone and/or isopropyl alcohol) to remove any debris and/or grease residue left from forming the shape of the metal layers 102. Additionally, one or more surfaces of the metal layers 102 can be etched to remove any oxide layers. Following the etching, the one or more surfaces of the metal layers 102 can be electropolished (e.g., using one or more commercially available solutions) to smooth the surfaces.
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At 1002, the method 1000 can comprise electroplating a metal enclosure (e.g., one or more metal layers 102) with a superconducting material (e.g., one or more superconducting material layers 104) to form a magnetic field shield. For example, the electroplating at 1002 can be performed in accordance with the first and/or second stages of manufacturing described herein. For instance, oxide layers on the metal enclosure can be removed via one or more etching processes. Further, one or more surfaces of the metal enclosure can be electropolished so as to smooth the surfaces in preparation of depositing the superconducting material. In various embodiments, the electroplating can coat a film of the superconducting material (e.g., the one or more superconducting material layers 104) onto the metal enclosure (e.g., one or more metal layers 102), as described herein.
At 1004, the method 1000 can comprise depositing a radiation shield (e.g., one or more radiation shield layers 106) onto the superconducting material (e.g., superconducting material layers 104), wherein the metal enclosure (e.g. metal layers 102), superconducting material (e.g., superconducting material layers 104), and radiation shield (e.g., radiation shield layers 106) can form a multi-layer enclosure 100 that can shield one or more superconducting devices from a magnetic field and/or radiation. For instance, in one or more embodiments the radiation shield can be painted onto the superconducting material. The multi-layer enclosure 100 formed at 1004 can exhibit magnetic field and/or radiation shielding while also exhibiting thermal conductivity properties conducive to operation of the one or more superconducting devices. For example, the metal enclosure (e.g., one or more metal layers 102) can enable the multi-layer enclosure 100 to cool rapidly to meet the temperature conditions that are optimal for operating the one or more superconducting devices.
At 1102, the method 1100 can comprise electroplating a metal enclosure (e.g., one or more metal layers 102) with a superconducting material (e.g., one or more superconducting material layers 104) to form a magnetic field shield. For example, the electroplating at 1102 can be performed in accordance with the first and/or second stages of manufacturing described herein. For instance, oxide layers on the metal enclosure can be removed via one or more etching processes. Further, one or more surfaces of the metal enclosure can be electropolished so as to smooth the surfaces in preparation of depositing the superconducting material. In various embodiments, the electroplating can coat a film of the superconducting material (e.g., the one or more superconducting material layers 104) onto the metal enclosure (e.g., one or more metal layers 102), as described herein.
At 1104, the method 1100 can comprise depositing a radiation shield (e.g., one or more radiation shield layers 106) onto the superconducting material (e.g., superconducting material layers 104), wherein the metal enclosure (e.g. metal layers 102), superconducting material (e.g., superconducting material layers 104), and radiation shield (e.g., radiation shield layers 106) can form a multi-layer enclosure 100 that can shield one or more superconducting devices from a magnetic field and/or radiation. For instance, in one or more embodiments the radiation shield can be painted and/or sprayed onto the superconducting material. The multi-layer enclosure 100 formed at 1104 can exhibit magnetic field and/or radiation shielding while also exhibiting thermal conductivity properties conducive to operation of the one or more superconducting devices. For example, the metal enclosure (e.g., one or more metal layers 102) can enable the multi-layer enclosure 100 to cool rapidly to meet the temperature conditions that are optimal for operating the one or more superconducting devices.
At 1106, the method 1100 can comprise providing a cryogenic magnetic shield (e.g., cryogenic magnetic shielding layers 202) onto the radiation shield (e.g., radiation shielding layers 106). For example, the depositing at 1106 can be performed in accordance with the fourth stage of manufacturing described herein. For instance, one or more sheets of the cryogenic magnetic shield can be welded together and wrapped light-tight around the radiation shield (e.g., radiation shield layers 106).
At 1108, the method 1100 can comprise providing a superinsulation material (e.g., one or more superinsulation layers 204) onto the cryogenic magnetic shield (e.g., one or more cryogenic magnetic shielding layers 202). The superinsulation material can comprise at least one member selected from a group consisting of: aluminized mylar film (e.g., having an exemplary thickness of 125 microns), aluminum foil (e.g., high purity foil with low emissivity qualities that enable superinsulation below 77 degrees Kalvin and/or having an exemplary nominal thickness of 0.08 mm), a superinsulated film with a vacuum deposited aluminum layer deposited on one or two sides of the film to approximately 400 angstrom to provide an effective radiation barrier. For example, the depositing at 1108 can be performed in accordance with the fifth stage of manufacturing described herein. The cryogenic magnetic shield and/or superinsulation material deposited at 1106 and/or 1108 can widen the temperature range at which the multi-layer enclosure 100 can provide shielding against magnetic fields and/or radiation.
In addition, the term “or” is intended to mean an inclusive “or” rather than an exclusive “or.” That is, unless specified otherwise, or clear from context, “X employs A or B” is intended to mean any of the natural inclusive permutations. That is, if X employs A; X employs B; or X employs both A and B, then “X employs A or B” is satisfied under any of the foregoing instances. Moreover, articles “a” and “an” as used in the subject specification and annexed drawings should generally be construed to mean “one or more” unless specified otherwise or clear from context to be directed to a singular form. As used herein, the terms “example” and/or “exemplary” are utilized to mean serving as an example, instance, or illustration. For the avoidance of doubt, the subject matter disclosed herein is not limited by such examples. In addition, any aspect or design described herein as an “example” and/or “exemplary” is not necessarily to be construed as preferred or advantageous over other aspects or designs, nor is it meant to preclude equivalent exemplary structures and techniques known to those of ordinary skill in the art.
It is, of course, not possible to describe every conceivable combination of components, products and/or methods for purposes of describing this disclosure, but one of ordinary skill in the art can recognize that many further combinations and permutations of this disclosure are possible. Furthermore, to the extent that the terms “includes,” “has,” “possesses,” and the like are used in the detailed description, claims, appendices and drawings such terms are intended to be inclusive in a manner similar to the term “comprising” as “comprising” is interpreted when employed as a transitional word in a claim. The descriptions of the various embodiments have been presented for purposes of illustration, but are not intended to be exhaustive or limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The terminology used herein was chosen to best explain the principles of the embodiments, the practical application or technical improvement over technologies found in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein.
