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Title: Terahertz conductivity of monolayer MoS$$_2$$
We calculate the electrical conductivity of suspended and supported monolayer MoS2 at terahertz (THz) frequencies by means of EMC–FDTD, a multiphysics simulation tool combining an ensemble Monte Carlo (EMC) solver for electron transport and a finite-difference time-domain (FDTD) solver for full-wave electrodynamics. We investigate the role of carrier and impurity densities, as well as substrate choice (SiO2 or hexagonal boron nitride, hBN), in frequency-dependent electronic transport. Owing to the dominance of surface-optical-phonon scattering, MoS2 on SiO2 has the lowest static conductivity, but also the weakest overall frequency dependence of the conductivity. In fact, at high THz frequencies, the conductivity of MoS2 on SiO2 exceeds that of either suspended or hBN-supported MoS2. We extract the parameters for Drude-model fits to the conductivity versus frequency curves obtained from microscopic simulation, which may aid in the experimental efforts toward MoS2 THz applications.  more » « less
Award ID(s):
2212011
PAR ID:
10462111
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Journal of Computational Electronics
ISSN:
1569-8025
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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