Qubits on solid state devices could potentially provide the rapid control necessary for developing scalable quantum information processors. Materials innovation and design breakthroughs have increased functionality and coherence of qubits substantially over the past two decades. Here, we show by improving interface between InAs as a semiconductor and Al as a superconductor, one can reliably fabricate voltage-controlled Josephson junction field effect transistor (JJ-FET) that can be used as tunable qubits, resonators, and coupler switches. We find that bandgap engineering is crucial in realizing a two-dimensional electron gas near the surface. In addition, we show how the coupling between the semiconductor layer and the superconducting contacts can affect qubit properties. We present the anharmonicity and coupling strengths from one and two-photon absorption in a quantum two level system fabricated with a JJ-FET.

中文翻译：

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用于超导量子电路的外延超导体-半导体二维系统

固态设备上的Qubit可能会提供开发可伸缩的量子信息处理器所需的快速控制。在过去的二十年中，材料创新和设计突破极大地提高了量子位的功能性和一致性。在这里，我们显示出通过改善InAs作为半导体与Al作为超导体之间的界面，可以可靠地制造出电压可调的约瑟夫森结型场效应晶体管（JJ-FET），该晶体管可用作可调量子位，谐振器和耦合器开关。我们发现，带隙工程对于在表面附近实现二维电子气至关重要。此外，我们展示了半导体层与超导触点之间的耦合如何影响量子位特性。