Rashba Effect and Raman Spectra of Tl$_2$O/PtS$_2$ Heterostructure

TL;DR

This study uses first-principles calculations to analyze the electronic, spintronic, and vibrational properties of the Tl$_2$O/PtS$_2$ heterostructure, revealing strong interlayer interactions, Rashba spin-splitting, and Raman spectra predictions for potential spintronics applications.

Contribution

First-principles investigation of Tl$_2$O/PtS$_2$ heterostructure's electronic, spintronic, and vibrational properties, including Rashba effects and Raman spectra, providing new insights into 2D spintronics materials.

Findings

Strong interlayer binding energy of -0.38 eV per unit cell.

Observation of Rashba spin-splitting in the valence band.

Calculated Raman spectra for Tl$_2$O and heterostructure.

Abstract

The possibility to achieve charge-to-spin conversion via Rashba spin-orbit effects provide stimulating opportunities toward the development of nanoscale spintronics. Here we use first-principles calculations to study the electronic and spintronic properties of Tl$_2$O/PtS$_2$ heterostructure, for which we have confirmed the dynamical stability by its positive phonon frequencies. An unexpectedly high binding energy of -0.38 eV per unit cell depicts strong interlayer interactions between Tl$_2$O and PtS$_2$. Interestingly, we discover Rashba spin-splitting's (with large $\alpha_R$ value) in the valence band of Tl$_2$O stemming from interfacial spin-orbit effects caused by PtS$_2$. The role of van der Waals binding on the orbital rearrangements has been studied using electron localization function and atomic orbital projections, which explains in detail the electronic dispersion near the Fermi level. Moreover, we explain the distinct band structure alignment in momentum space but separation in real space of Tl$_2$O/PtS$_2$ heterostructure. Since 2D Tl$_2$O still awaits experimental confirmation, we calculate, for the first time, the Raman spectra of pristine Tl$_2$O and the Tl$_2$O/PtS$_2$ heterostructure and discuss peak positions corresponding to vibrational modes of the atoms. These findings offer a promising avenue to explore spin physics for potential spintronics applications via 2D heterostructures.