All-Mechanical Control of Single Electrons

I. Peterson

Mauro Ballicchia, Mihail Nedjalkov, Josef Weinbub

Double-well potential structures provide rich capabilities for single electron control via different physical characteristics of the potentials and the electron state. Here, we investigate the effect of a uniform magnetic field on the electron state interference pattern manifesting in a focusing double-well potential structure by conducting Wigner quantum transport experiments. We analyze the electron density and the negativity of the Wigner function and show how the magnetic field controls the electron state but also destroys the coherence of the evolution dynamics. Our work contributes to the fundamental understanding of magnetic field based single electron control mechanisms and sheds light on the critical decoherence processes.

Sungguen Ryu, Rosa López, Llorenç Serra +2 more

Identifying and controlling decoherence in single-electron sources (SESs) is important for their applications in quantum information processing. The recent experiments with ultrashort electron pulses [J. D. Fletcher et al., Nat. Commun. 10, 5298 (2019)] demonstrate strong decoherence that cannot be caused by traditional mechanisms such as electron-electron or electron-phonon interactions. Here we propose timing noise as a universal model, consistent with existing experimental data, to explain strong decoherence of ultrafast SES pulses, without resorting to any specific microscopic mechanism for such decoherence. We also propose a protocol to filter out timing noise which works even in the presence of other decoherence effects, such as those present in, e.g., low-energy SESs.

Alexander F. Otte

This paper addresses sub-Poissonian electronic and photonic noise generation in semiconductor junctions. Recent theoretical and technical advances in the understanding and generation of quantum noise-suppressed (‘quiet’) light have emphasised the links between photonic and electronic shot noise. Shot-noise suppression and single electron–photon control through the operation of the collective and single-electron Coulomb blockade mechanisms are described.