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arXiv · 1904.09009

Electrical control of magnetization in S/F/S junctions on a 3D topological insulator

M. Nashaat·I. V. Bobkova·A. M. Bobkov·Yu. M. Shukrinov·I. R. Rahmonov·K. Sengupta
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Abstract

Strong dependence of the Josephson energy on the magnetization orientation in Josephson junctions with ferromagnetic interlayers and spin-orbit coupling opens a way to control magnetization by Josephson current or Josephson phase. Here we investigate the perspectives of magnetization control in superconductor/ferromagnet/superconductor (S/F/S) Josephson junctions on the surface of a 3D topological insulator hosting Dirac quasiparticles. Due to the spin-momentum locking of these Dirac quasiparticles a strong dependence of the Josephson current-phase relation on the magnetization orientation is realized. It is demonstrated that this can lead to splitting of the ferromagnet's easy-axis in the voltage driven regime. We show that such a splitting can lead to stabilization of an unconventional four-fold degenerate ferromagnetic state.

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M. Nashaat, I. V. Bobkova, A. M. Bobkov, Yu. M. Shukrinov, I. R. Rahmonov, K. Sengupta. 2019-08-09. Electrical control of magnetization in S/F/S junctions on a 3D topological insulator. https://doi.org/10.1103/physrevb.100.054506

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