Quantum ground state control in superconductor-silicene structures: $0$-$\pi$ transitions, $\varphi_0$-junctions, and Majorana bound states

TL;DR

This paper theoretically explores how proximity-induced superconductivity in silicene enables electrical control of quantum states, including $0$-$ o$-$ ext{pi}$ transitions, $ ext{phi}_0$-junctions, and Majorana bound states, with potential applications in quantum computing.

Contribution

It introduces novel mechanisms for controlling quantum ground states in silicene-based superconducting structures through electric and magnetic fields, including the realization of Majorana states.

Findings

Electric field induces $0$-$ ext{pi}$ transitions in silicene Josephson junctions.

Zigzag interfaces cause $ ext{phi}_0$ states due to intervalley scattering.

Majorana bound states are tunable via edge orientation and external fields.

Abstract

We demonstrate theoretically that proximity-induced superconductivity in silicene offers the possibility to exert strong quantum ground state control. We show that electrically controlled $0$-$\pi$ transitions occur in Josephson junctions in the presence of an exchange field due to the buckling of the silicene lattice. We also discover that zigzag-oriented interfaces, featuring intervalley scattering, cause a $\varphi_0$ state with an applied electric field. Finally, we demonstrate that Majorana bound states along the silicene edge are tunable via the edge orientation, electric, and in-plane spin exchange fields.