Manipulation with spin of Andreev levels

Start date 01/01/2006
Josephson junction with spin-active nanowire 
 
Recent  advances in the development and experimental investigation of nanowire based Josephson junctions attracts new attention to the rich physics of the mesoscopic Josephson effect. One of the particularly interesting questions concernes the possibility to employ the Josephson quantum point contacts for information processing. Such contacts contain a small number of fermionic two-level systems - Andreev Bound States. Our group has previously proposed to use such states as qubits [1], the manipulation of which is performed by temporal modulation of the superconducting phase-difference across the junction.
We now investigate methods of manipulation with the Andreev bound states in Josephson quantum point contacts containing a magnetic scatterer, e.g. magnetic nanoparticle situating between the superconducting electrodes , Fig 1 [2]. The Andreev level subsystem in such junctions can, contrary to non-magnetic junctions, have a finite ground state spin-polarization, which allows a way of manipulation by resonantly driving the direction of magnetic moment of the scatterer resulting in temporal oscillation of the Josephson current and Andreev state spin polarization.
 
 
​SSF-OXIDE, Swedich Research Council (VR)

Published: Thu 09 Feb 2017.