Electrically tunable magnetoplasmons in a monolayer of silicene or germanene

TL;DR

This paper theoretically investigates how external electric fields and strong spin-orbit coupling influence magnetoplasmon behavior in monolayer silicene and germanene, with implications for future spintronics and optoelectronics.

Contribution

It derives the dynamical response function considering SOC and electric field effects, extending understanding of magnetoplasmon spectra in these 2D materials.

Findings

Dispersion relation similar to 2D electron gas with modified frequencies

Results align with graphene experiments without SOC and electric field

Predicted effects can be tested in future experiments

Abstract

We theoretically study electrically tunable magnetoplasmons in a monolayer of silicene or germanene. We derive the dynamical response function and take into account the effects of strong spin-orbit coupling (SOC) and of an external electric filed $E_z$ perpendicular to the plane of the buckled silicene/germanene. Employing the random-phase approximation we analyze the magnetoplasmon spectrum. The dispersion relation has the same form as in a two-dimensional electron gas with the cyclotron and plasma frequencies modified due to the SOC and the field $E_z$. In the absence of SOC and $E_z$, our results agree well with recent experiments on graphene. The predicted effects could be tested by experiments similar to those on graphene and would be useful for future spintronics and optoelectronic devices.