English

Andreev spin-noise detector

Superconductivity 2023-10-09 v2 Mesoscale and Nanoscale Physics

Abstract

We investigate the possibility to employ magnetic Josephson junctions as magnetic-noise detectors. To illustrate our idea, we consider a system consisting of a quantum dot coupled to superconducting leads in the presence of an external magnetic field. Under appropriate assumptions, we relate the noise in the Josephson current to magnetization noise. At the magnetic field driven 0π0-\pi transition the junction sensitivity as magnetic noise detector is strongly enhanced and it diverges in the zero temperature limit. Moreover, we demonstrate that, if also dot energy is affected by fluctuations, only the magnetic noise channel contributes to Josephson current noise response when the quantum dot is tuned in resonance with superconducting leads.

Keywords

Cite

@article{arxiv.2308.01995,
  title  = {Andreev spin-noise detector},
  author = {Roberto Capecelatro and Valentina Brosco and Gabriele Campagnano and Procolo Lucignano},
  journal= {arXiv preprint arXiv:2308.01995},
  year   = {2023}
}

Comments

Review. 14 pages. 3 appendices. 14 figures

R2 v1 2026-06-28T11:47:41.169Z