Zero-Phase-Difference Josephson Current Based on Spontaneous Symmetry Breaking via Parametric Excitation of a Movable Superconducting Dot
Artikel i vetenskaplig tidskrift, 2017

Recent advances have attracted attention to nonstandard Josephson junctions in which a supercurrent can flow despite zero phase difference between the constituent superconducting leads. Here, we propose a zero-phase-difference nanoelectromechanical junction which, in contrast to other considered systems, exhibits symmetry between leftward and rightward tunneling through the junction. We show that a supercurrent is, nevertheless, possible as a result of spontaneous symmetry breaking. In the suggested junction, the supercurrent is mediated by tunneling via a superconducting Cooper-pair box on a mechanical resonator. An alternating electric potential parametrically excites mechanical oscillations which are synchronized with charge oscillations of the box. This leads to coherent transfer of Cooper pairs through the junction. The direction of the supercurrent is a result of spontaneous symmetry breaking and thus it can be reversed without changing the parameters.

superconductivity

nanoelectromechanical systems

Cooper-pair box

Författare

Martin Eriksson

Chalmers, Fysik, Kondenserade materiens teori

Anton Vikström

Chalmers, Fysik, Kondenserade materiens teori

Physical Review Letters

0031-9007 (ISSN) 1079-7114 (eISSN)

Vol. 118 197701- 197701

Styrkeområden

Nanovetenskap och nanoteknik

Ämneskategorier

Den kondenserade materiens fysik

DOI

10.1103/PhysRevLett.118.197701

PubMed

28548522