Momentum-Space Josephson Effects

The Josephson effect is a prominent phenomenon of quantum supercurrents that has been widely studied in superconductors and superfluids. Typical Josephson junctions consist of two real-space superconductors (superfluids) coupled through a weak tunneling barrier. Here we propose a momentum-space Jose...

Full description

Saved in:
Bibliographic Details
Published inPhysical review letters Vol. 120; no. 12; p. 120401
Main Authors Hou, Junpeng, Luo, Xi-Wang, Sun, Kuei, Bersano, Thomas, Gokhroo, Vandna, Mossman, Sean, Engels, Peter, Zhang, Chuanwei
Format Journal Article
LanguageEnglish
Published United States 23.03.2018
Online AccessGet more information

Cover

More Information
Summary:The Josephson effect is a prominent phenomenon of quantum supercurrents that has been widely studied in superconductors and superfluids. Typical Josephson junctions consist of two real-space superconductors (superfluids) coupled through a weak tunneling barrier. Here we propose a momentum-space Josephson junction in a spin-orbit coupled Bose-Einstein condensate, where states with two different momenta are coupled through Raman-assisted tunneling. We show that Josephson currents can be induced not only by applying the equivalent of "voltages," but also by tuning tunneling phases. Such tunneling-phase-driven Josephson junctions in momentum space are characterized through both full mean field analysis and a concise two-level model, demonstrating the important role of interactions between atoms. Our scheme provides a platform for experimentally realizing momentum-space Josephson junctions and exploring their applications in quantum-mechanical circuits.
ISSN:1079-7114
DOI:10.1103/PhysRevLett.120.120401