English

Signatures of odd-frequency pairing in the Josephson junction current noise

Mesoscale and Nanoscale Physics 2020-11-11 v1 Superconductivity

Abstract

Odd frequency (odd-ω\omega) electron pair correlations naturally appear at the interface between BCS superconductors and other materials. The detection of odd-ω\omega pairs, which are necessarily non-local in time, is still an open problem. The main reason is that they do not contribute to static measurements described by time-local correlation functions. Therefore, dynamical measurements, which depend on non-local time correlations, are suitable for detecting these pairs. In this work, we study the signatures of odd-ω\omega pairs in the supercurrent noise through a weak link between two superconductors at different superconducting phases. We show that the finite frequency current noise can be decomposed into three different contributions coming from even frequency (even-ω\omega), odd-ω\omega pair amplitudes, and electron-hole correlation functions. Odd-ω\omega pairing, which is inter-lead (between electrons at different sides of the junction), provides a positive contribution to the noise, becoming maximal at a superconducting phase difference of π\pi. In contrast, intra-lead even-ω\omega pair amplitude tends to reduce the noise, except for a region close to π\pi, controlled by the transmission of the junction.

Keywords

Cite

@article{arxiv.2008.00237,
  title  = {Signatures of odd-frequency pairing in the Josephson junction current noise},
  author = {R. Seoane Souto and D. Kuzmanovski and A. V. Balatsky},
  journal= {arXiv preprint arXiv:2008.00237},
  year   = {2020}
}

Comments

11 pages, 5 figures