Nonequilibrium effects in a Josephson junction coupled to a precessing spin
Artikel i vetenskaplig tidskrift, 2011

We present a theoretical study of a Josephson junction consisting of two s-wave superconducting leads coupled over a classical spin. When an external magnetic field is applied, the classical spin will precess with the Larmor frequency. This magnetically active interface results in a time-dependent boundary condition with different tunneling amplitudes for spin-up and spin-down quasiparticles and where the precession produces spin-flip scattering processes. We show that as a result, the Andreev states develop sidebands and a nonequilibrium population which depend on the precession frequency and the angle between the classical spin and the external magnetic field. The Andreev states lead to a steady-state Josephson current whose current-phase relation could be used for characterizing the precessing spin. In addition to the charge transport, a magnetization current is also generated. This spin current is time dependent and its polarization axis rotates with the same precession frequency as the classical spin.

boundary-conditions

multilayer

heterostructures

superconductivity

transport

active interfaces

spintronics

single-molecule magnets

quasi-classical theory

spectroscopy

Författare

Cecilia Holmqvist

Chalmers, Mikroteknologi och nanovetenskap (MC2), Tillämpad kvantfysik

S. Teber

Mikael Fogelström

Chalmers, Mikroteknologi och nanovetenskap (MC2), Tillämpad kvantfysik

Physical Review B - Condensed Matter and Materials Physics

1098-0121 (ISSN)

Vol. 83 10

Ämneskategorier

Fysik

DOI

10.1103/PhysRevB.83.104521