A comprehensive study of complex non-adiabatic exciton dynamics in MoSiN
arXiv:2208.09384 · doi:10.1016/j.mtphys.2022.100814
Abstract
Excitons, which are composite boson quasi-particles composed of bound electrons and holes, have many fascinating properties and great potential in practical applications. Though experimental studies on exciton dynamics are well-developed, the ab initio simulation ones still remain vacant until two years ago. Here, we apply the density functional theory (DFT) and many-body perturbation theory (MBPT) on 2D MoSiN to study its exciton-related physics and non-adiabatic ultrafast exciton dynamics theoretically and numerically for the first time. We calculate the photoluminescence (PL) spectra with final states as bright excitons, yet lots of them are contributed by the dark ones, and the results match the experimental ones perfectly. We also study the dark-exciton-involved processes, which were barely studied in the past but dominate in many physical processes, and obtain several main results like: (i) High scattering rates over the whole Brillouin zone (BZ) within the order of magnitude from 10 fs to 10 fs; (ii) Thorough analysis for the dynamics of the dark excitons at valley, which have negative effective mass and the highest scattering rate among several exciton states; (iii) Simulate the time-resolved evolution of the excitons after photo-excitation with the real-time Boltzmann transport equation (rt-BTE) techniques, in which process excitons at K/K' valley play an important role; (iv) Exciton dynamics with spin-valley locking at K/K' valley are also discussed here; (v) A new approach is proposed for modulating the non-adiabatic effects for excitons, accompanied by a chiral phonon absorption/emission, by tuning the chirality of the external circularly polarized light. All the results show that the 2D material MoSiN is an ideal platform to study the exciton-involved physics and has great application value.
arXiv comment8 pages, 5 figures
References in corpus (24)
- Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
- Exciton Binding Energy and Nonhydrogenic Rydberg Series in Monolayer WS2
- Observation of giant bandgap renormalization and excitonic effects in a monolayer transition metal dichalcogenide semiconductor
- Optimization Algorithm for the Generation of ONCV Pseudopotentials
- Yambo: an \textit{ab initio} tool for excited state calculations
- Exceptional piezoelectricity, high thermal conductivity and stiffness and promising photocatalysis in two-dimensional MoSi2N4 family confirmed by first-principles
- Many-body perturbation theory calculations using the yambo code
- Control of interlayer excitons in two-dimensional van der Waals heterostructures
- MoSi2N4 single-layer: a novel two-dimensional material with outstanding mechanical, thermal, electronic, optical, and photocatalytic properties
- Excitons versus electron-hole plasma in monolayer transition metal dichalcogenide semiconductors
- {\it Ab--initio} finite temperature excitons
- Breakdown of optical phonons' splitting in two-dimensional materials
- First-principles dynamics of electrons and phonons
- Exciton-exciton interaction in transition metal dichalcogenide monolayers and van der Waals heterostructures
- Intrinsic piezoelectricity in monolayer (X=Ti, Zr, Hf, Cr, Mo and W)
- Electron-exciton interactions in the exciton-polaron problem
- Exciton-phonon coupling in the UV absorption and emission spectra of bulk hexagonal boron nitride
- Theory of phonon-assisted luminescence in solids: application to hexagonal boron nitride
- Bright excitons with negative-mass electrons
- Chiral phonons and pseudo-angular momentum in non-symmorphic systems
- Two-dimensional MoSi2N4: An Excellent 2D Semiconductor for Transistors
- Crystallization of an exciton superfluid
- Harnessing Exciton-Exciton Annihilation in Two-Dimensional Semiconductors
- Critical point for Bose-Einstein condensation of excitons in graphite