# An effective model for the electronic and optical properties of stanene

## TL;DR

This paper introduces a simple, reliable quadratic effective model for stanene's electronic and optical properties up to 1.1 eV, simplifying calculations while maintaining accuracy for low-energy phenomena.

## Contribution

The authors develop and validate a quadratic effective model for stanene that accurately describes its low-energy electronic and optical properties, reducing computational complexity.

## Key findings

- Quadratic model best fits stanene bandstructure data
- Neglecting lattice buckling is justified for bandstructure calculations
- Circularly polarized light selectively excites spins in stanene

## Abstract

The existence of several 2D materials with heavy atoms in their composition has been recently demonstrated. The electronic and optical properties of these materials can be accurately computed with numerically intensive density functional theory methods. However, it is desirable to have simple effective models that can accurately describe these properties at low energies. Here we present an effective model for stanene that is reliable for electronic and optical properties for photon energies up to 1.1 eV. For this material, we find that a quadratic model with respect to the lattice momentum is the best suited for calculations based on the bandstructure, even with respect to band warping. We also find that splitting the two spin-z subsectors is a good approximation, which indicates that the lattice buckling can be neglected in calculations based on the bandstructure. We illustrate the applicability of the model by computing the linear optical injection rates of carrier and spin densities in stanene. Our calculations indicate that an incident circularly polarized optical field only excites electrons with spin that matches its helicity.