Jang Wonjin, Cho Min-Kyun, Jang Hyeongyu, Kim Jehyun, Park Jaemin, Kim Gyeonghun, Kang Byoungwoo, Jung Hwanchul, Umansky Vladimir, Kim Dohun
Department of Physics and Astronomy and Institute of Applied Physics, Seoul National University, Seoul 08826, Korea.
Department of Physics, Pusan National University, Busan 46241, Korea.
Nano Lett. 2021 Jun 23;21(12):4999-5005. doi: 10.1021/acs.nanolett.1c00783. Epub 2021 Jun 10.
We report a single-shot-based projective readout of a semiconductor hybrid qubit formed by three electrons in a GaAs double quantum dot. Voltage-controlled adiabatic transitions between the qubit operations and readout conditions allow high-fidelity mapping of quantum states. We show that a large ratio both in relaxation time vs tunneling time (≈50) and singlet-triplet splitting vs thermal energy (≈20) allows energy-selective tunneling-based spin-to-charge conversion with a readout visibility of ≈92.6%. Combined with ac driving, we demonstrate high visibility coherent Rabi and Ramsey oscillations of a hybrid qubit in GaAs. Further, we discuss the generality of the method for use in other materials, including silicon.
我们报道了基于单次测量的由砷化镓双量子点中的三个电子形成的半导体混合量子比特的投影读出。量子比特操作与读出条件之间的电压控制绝热跃迁实现了量子态的高保真映射。我们表明，弛豫时间与隧穿时间之比（约为50）以及单重态 - 三重态分裂与热能之比（约为20）都很大，这使得基于能量选择性隧穿的自旋 - 电荷转换的读出可见度约为92.6%。结合交流驱动，我们展示了砷化镓中混合量子比特的高可见度相干拉比振荡和拉姆齐振荡。此外，我们讨论了该方法在包括硅在内的其他材料中的通用性。
