6533b7d8fe1ef96bd126b75f
RESEARCH PRODUCT
Quantum fluctuations and coherence in high-precision single-electron capture.
Janis TimoshenkoVyacheslavs Kashcheyevssubject
Quantum phase transitionPhysicsCondensed Matter - Mesoscale and Nanoscale PhysicsQuantum limitFOS: Physical sciencesGeneral Physics and AstronomyQuantum phasesQuantum imagingQuantum stateQuantum mechanicsQuantum processMesoscale and Nanoscale Physics (cond-mat.mes-hall)Amplitude damping channelQuantum fluctuationdescription
The phase of a single quantum state is undefined unless the history of its creation provides a reference point. Thus quantum interference may seem hardly relevant for the design of deterministic single-electron sources which strive to isolate individual charge carriers quickly and completely. We provide a counterexample by analyzing the non-adiabatic separation of a localized quantum state from a Fermi sea due to a closing tunnel barrier. We identify the relevant energy scales and suggest ways to separate the contributions of quantum non-adiabatic excitation and backtunneling to the rare non-capture events. In the optimal regime of balanced decay and non-adiabaticity, our simple electron trap turns into a single-lead Landau-Zener-backtunneling interferometer, revealing the dynamical phase accumulated between the particle capture and leakage. The predicted "quantum beats in backtunneling" may turn the error of a single-electron source into a valuable signal revealing essentially non-adiabatic energy scales of a dynamic quantum dot.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2012-05-17 | Physical review letters |