Naslov
Raman features of graphene and Weyl semimetals beyond the standard nonadiabatic theory

Autori
Girotto, Nina ; Novko, Dino

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, neobjavljeni rad, znanstveni

Skup
PSI-k 2022 conference

Mjesto i datum
Lausanne, Švicarska, 22.08.2022. - 25.08.2022

Vrsta sudjelovanja
Poster

Vrsta recenzije
Nije recenziran

Ključne riječi
Raman spectrum, linewidth, temperature, phonon, electron-phonon interaction, DFT, nonadiabaticity, 2D materials

Sažetak
Although graphene has already been thoroughly studied with Raman spectroscopy, there still exists a disagreement about the broadening mechanisms of the E2g mode and its actual temperature dependence [Nano Lett. 10, 466 (2010)]. Along with the importance of the nonadiabatic effects in graphene, higher order electron-phonon scattering processes also significantly impact the phonon spectrum. Specifically, the electron- phonon-induced lifetime and energy renormalization of the electron-hole pair excitations bring additional temperature dependence in the electron- coupled phonon modes and their corresponding linewidths. The nonadiabatic theory relying on first principles calculations, developed in [Phys. Rev. B 98, 041112(R) (2018)], is here successfully applied to graphene in various doping regimes and to Weyl semimetals, which contain a 3-dimensional analog of Dirac points in the electron band structure and are, therefore, excellent candidates for achieving a nonadiabatic regime.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

POVEZANOST RADA