Ab initio real-time quantum dynamics of charge carriers in momentum space.
Nat Comput Sci
; 3(6): 532-541, 2023 Jun.
Article
in En
| MEDLINE
| ID: mdl-38177418
ABSTRACT
Application of the non-adiabatic molecular dynamics (NAMD) approach is limited to studying carrier dynamics in the momentum space, as a supercell is required to sample the phonon excitation and electron-phonon (e-ph) interaction at different momenta in a molecular dynamics simulation. Here we develop an ab initio approach for the real-time charge carrier quantum dynamics in the momentum space (NAMD_k) by directly introducing e-ph coupling into the Hamiltonian based on the harmonic approximation. The NAMD_k approach maintains the zero-point energy and includes memory effects of carrier dynamics. The application of NAMD_k to the hot carrier dynamics in graphene reveals the phonon-specific relaxation mechanism. An energy threshold of 0.2 eV-defined by two optical phonon modes-separates the hot electron relaxation into fast and slow regions with lifetimes of pico- and nanoseconds, respectively. The NAMD_k approach provides an effective tool to understand real-time carrier dynamics in the momentum space for different materials.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Electrons
/
Graphite
Language:
En
Journal:
Nat Comput Sci
Year:
2023
Document type:
Article
Affiliation country:
China
Country of publication:
United States