Modelling ultrafast non-equilibrium carrier dynamics and relaxation processes upon irradiation of hexagonal Silicon-Carbide with femtosecond laser pulses

• Main Authors: Tsibidis, G. D, Mouchliadis, L, Pedio, M, Stratakis, E
• Format: Journal Article
• Language: English
• Published: 10-02-2020
• Subjects: Physics - Materials Science
• DOI: 10.48550/arxiv.1910.14501

Phys. Rev. B 101, 075207 (2020) We present a theoretical investigation of the yet unexplored dynamics of the
produced excited carriers upon irradiation of hexagonal Silicon Carbide
(6H-SiC) with femtosecond laser pulses. To describe the ultrafast behaviour of
laser induced out-of-equilibrium carriers, a real time simulation based on
Density Functional Theory (DFT) methodology is used to compute both the hot
carrier dynamics and transient change of the optical properties. A
Two-Temperature model (TTM) is also employed to derive the relaxation processes
for laser pulses of wavelength 401 nm, duration 50 fs at normal incidence
irradiation which indicate that surface damage on the material occurs for
fluence ~1.88 Jcm-2. This approach of linking, for the first time, real time
calculations, transient optical properties and TTM modelling, has strong
implications for understanding both the ultrafast dynamics and relaxation
processes and providing a precise investigation of the impact of hot carrier
population in surface damage mechanisms in solids.