Effective Land\'{e} factors for an electrostatically defined quantum point contact in silicene

TL;DR

This study investigates the effective Landé g-factors in a silicene quantum point contact, revealing how spin-orbit coupling and magnetic field orientation influence Zeeman splitting and g* values.

Contribution

It provides new insights into the Landé g-factors in silicene quantum point contacts, highlighting the effects of spin-orbit coupling and edge geometry on magnetic response.

Findings

g* factor reduces from 2 to 0.45 for in-plane fields across subbands

g* enhances to 5.8 (zigzag) and 2.5 (armchair) for perpendicular fields

Intrinsic spin-orbit coupling dominates Zeeman splitting

Abstract

The transconductance and effective Land\'{e} $g^*$ factors for a quantum point contact defined in silicene by the electric field of a split gate is investigated. The strong spin-orbit coupling in buckled silicene reduces the $g^*$ factor for in-plane magnetic field from the nominal value 2 to around 1.2 for the first- to 0.45 for the third conduction subband. However, for perpendicular magnetic field we observe an enhancement of $g^*$ factors for the first subband to 5.8 in nanoribbon with zigzag and to 2.5 with armchair edge. The main contribution to the Zeeman splitting comes from the intrinsic spin-orbit coupling defined by the Kane-Mele form of interaction.