Wozniak, Tomasz and Umm-e-hani, Paulo E. and Faria Junior, Paulo E. and Ramzan, Muhammad B. and Kuc, Agnieszka (2023) Electronic and Excitonic Properties of MSi₂Z₄ Monolayers. SMALL, 19 (19). p. 2206444. ISSN 1613-6810, 1613-6829
Full text not available from this repository. (Request a copy)Abstract
MA(2)Z(4) monolayers form a new class of hexagonal non-centrosymmetric materials hosting extraordinary spin-valley physics. While only two compounds (MoSi2N4 and WSi2N4) are recently synthesized, theory predicts interesting (opto)electronic properties of a whole new family of such two-dimensional (2D) materials. Here, the chemical trends of band gaps and spin-orbit splittings of bands in selected MSi(2)Z(4) (M = Mo, W; Z = N, P, As, Sb) compounds are studied from first-principles. Effective Bethe-Salpeter-equation-based calculations reveal high exciton binding energies. Evolution of excitonic energies under external magnetic field is predicted by providing their effective g-factors and diamagnetic coefficients, which can be directly compared to experimental values. In particular, large positive g-factors are predicted for excitons involving higher conduction bands. In view of these predictions, MSi(2)Z(4) monolayers yield a new platform to study excitons and are attractive for optoelectronic devices, also in the form of heterostructures. In addition, a spin-orbit induced bands inversion is observed in the heaviest studied compound, WSi2Sb4, a hallmark of its topological nature.
| Item Type: | Article |
|---|---|
| Uncontrolled Keywords: | VALLEY POLARIZATION; 2D MA(2)Z(4) materials; density functional theory; excitons; g-factors; model Bethe-Salpeter equation |
| Subjects: | 500 Science > 530 Physics |
| Divisions: | Physics > Institute of Theroretical Physics |
| Depositing User: | Dr. Gernot Deinzer |
| Date Deposited: | 05 Apr 2024 06:49 |
| Last Modified: | 05 Apr 2024 06:49 |
| URI: | https://pred.uni-regensburg.de/id/eprint/60512 |
Actions (login required)
 |
View Item |
