Terahertz conductivity of monolayer MoS2

• Published in: Journal of computational electronics Vol. 22; no. 5; pp. 1319 - 1326
• Main Authors: Mitra, S., Avazpour, L., Knezevic, I.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-10-2023; Springer Nature B.V
• Subjects: Boron nitride; Boundary conditions; Carrier density; Electrical Engineering; Electrical resistivity; Electrodynamics; Electron transport; Electrons; Engineering; Finite difference time domain method; Magnetic fields; Mathematical and Computational Engineering; Mathematical and Computational Physics; Mechanical Engineering; Molybdenum disulfide; Monolayers; Optical and Electronic Materials; Silicon dioxide; Simulation; Solvers; Substrates; Terahertz frequencies; Theoretical; MoS; Electron–phonon scattering; Monte Carlo; Electronic transport; Conductivity; TMD; Terahertz; FDTD
• ISSN: 1569-8025; 1572-8137
• DOI: 10.1007/s10825-023-02023-x

We calculate the electrical conductivity of suspended and supported monolayer MoS
2
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 (SiO
2
or hexagonal boron nitride, hBN), in frequency-dependent electronic transport. Owing to the dominance of surface-optical-phonon scattering, MoS
2
on SiO
2
has the lowest static conductivity, but also the weakest overall frequency dependence of the conductivity. In fact, at high THz frequencies, the conductivity of MoS
2
on SiO
2
exceeds that of either suspended or hBN-supported MoS
2
. 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 MoS
2
THz applications.