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Coherent beam splitting of flying electrons driven by a surface acoustic wave

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 نشر من قبل Ryo Ito
 تاريخ النشر 2020
  مجال البحث فيزياء
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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.



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