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arXiv · 2309.17273

Characterizing losses in InAs two-dimensional electron gas-based gatemon qubits

William M. Strickland·Lukas J. Baker·Jaewoo Lee·Krishna Dindial·Bassel Heiba Elfeky·Patrick J. Strohbeen·Mehdi Hatefipour·Peng Yu·Ido Levy·Jacob Issokson·Vladimir E. Manucharyan·Javad Shabani
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Abstract

The tunnelling of cooper pairs across a Josephson junction (JJ) allow for the nonlinear inductance necessary to construct superconducting qubits, amplifiers, and various other quantum circuits. An alternative approach using hybrid superconductor-semiconductor JJs can enable superconducting qubit architectures with all electric control. Here we present continuous-wave and time-domain characterization of gatemon qubits and coplanar waveguide resonators based on an InAs two-dimensional electron gas. We show that the qubit undergoes a vacuum Rabi splitting with a readout cavity and we drive coherent Rabi oscillations between the qubit ground and first excited states. We measure qubit relaxation times to be $T_1 =$ 100 ns over a 1.5 GHz tunable band. We detail the loss mechanisms present in these materials through a systematic study of the quality factors of coplanar waveguide resonators. While various loss mechanisms are present in III-V gatemon circuits we detail future directions in enhancing the relaxation times of qubit devices on this platform.

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William M. Strickland, Lukas J. Baker, Jaewoo Lee, Krishna Dindial, Bassel Heiba Elfeky, Patrick J. Strohbeen, Mehdi Hatefipour, Peng Yu, Ido Levy, Jacob Issokson, Vladimir E. Manucharyan, Javad Shabani. 2023-09-29. Characterizing losses in InAs two-dimensional electron gas-based gatemon qubits. https://arxiv.org/abs/2309.17273

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