Coherent Beam Splitting of Flying Electrons Driven by a Surface Acoustic Wave

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.

Automated summary

A coherent beam splitter has been developed for single electrons passing through two tunnel-coupled quantum wires by surface acoustic waves (SAWs). The oscillation of output current with gate voltages allows for encoding a flying qubit, with oscillation visibility currently limited to around 3% but robust against decoherence. The SAW-driven single electrons show promise as a novel platform for a solid-state flying qubit.