Feature-rich electronic excitations in external fields of 2D silicene

TL;DR

This paper investigates electronic excitations in monolayer silicene under external fields using a new generalized tight-binding model, revealing tunable plasmon behaviors influenced by multiple interactions and external parameters.

Contribution

The study introduces a generalized tight-binding model that incorporates various interactions and external fields, providing detailed insights into plasmon behaviors in silicene.

Findings

Electrically tunable magnetoplasmons in silicene.

Magnetic field modulation of plasmon properties.

Enhanced tunability of plasmons via momentum transfer and Fermi energy.

Abstract

Electronic Coulomb excitations in monolayer silicene are investigated by using the Lindhard dielectric function and a newly developed generalized tight-binding model (G-TBM). G-TBM simultaneously contains the atomic interactions, the spin-orbit coupling, the Coulomb interactions, and the various external fields at an arbitrary chemical potential. We exhibit the calculation results of the electrically tunable magnetoplasmons and the strong magnetic field modulation of plasmon behaviors. The two intriguing phenomena are well explained by determining the dominant transition channels in the dielectric function and through understanding the electron behavior under the multiple interactions (intrinsic and external). A further tunability of the plasmon features is demonstrated with the momentum transfer and the Fermi energy. The methodological strategy could be extended to several other 2D materials like germanene and stanene, and might open a pathway to search a better system in nanoplasmonic applications.