Ito R, Takada S, Ludwig A, Wieck A D, Tarucha S, Yamamoto M
Center for Emergent Matter Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
National Institute of Advanced Industrial Science and Technology, National Metrology Institute of Japan, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8563, Japan.
Phys Rev Lett. 2021 Feb 19;126(7):070501. doi: 10.1103/PhysRevLett.126.070501.
We develop a coherent beam splitter for single electrons driven through two tunnel-coupled quantum wires by surface acoustic waves (SAWs). The output current through each wire oscillates with gate voltages to tune the tunnel coupling and potential difference between the wires. This oscillation is assigned to coherent electron tunneling motion that can be used to encode a flying qubit and is well reproduced by numerical calculations of time evolution of the SAW-driven single electrons. The oscillation visibility is currently limited to about 3%, but robust against decoherence, indicating that the SAW electron can serve as a novel platform for a solid-state flying qubit.
我们开发了一种用于单电子的相干分束器，该单电子由表面声波（SAW）驱动通过两条隧道耦合量子线。通过每条线的输出电流随栅极电压振荡，以调节线之间的隧道耦合和电势差。这种振荡归因于相干电子隧穿运动，该运动可用于编码飞行量子比特，并且通过SAW驱动单电子的时间演化数值计算得到了很好的再现。目前，振荡可见度限制在约3%，但对退相干具有鲁棒性，这表明SAW电子可作为固态飞行量子比特的新型平台。
