Spin-orbit coupling effect on electronic, optical, and thermoelectric properties of Janus GaSSe.

In this paper, we investigate the electronic, optical, and thermoelectric properties of GaSSe monolayer by using density functional theory. analysis of the phonon spectrum and molecular dynamics simulations, GaSSe is confirmed to be stable at room temperature. Our calculations demonstrate that GaSSe exhibits indirect semiconductor characteristics and the spin-orbit coupling (SOC) effect has slightly reduced its band gap. Besides, the band gap of GaSSe depends tightly on the biaxial strain. When the SOC effect is included, small spin-orbit splitting energy of 90 meV has been found in the valence band. However, the spin-orbit splitting energy dramatically changes in the presence of biaxial strain. GaSSe exhibits high optical absorption intensity in the near-ultraviolet region, up to 8.444 × 10 cm, which is needed for applications in optoelectronic devices. By using the Boltzmann transport equations, the electronic transport coefficients of GaSSe are comprehensively investigated. Our calculations reveal that GaSSe exhibits a very low lattice thermal conductivity and high figure of merit and we can enhance its by temperature. Our findings provide further insight into the physical properties of GaSSe as well as point to prospects for its application in next-generation high-performance devices.