Magneto‐optical properties of monolayer MoS₂‐SiO₂/Si structure measured via terahertz time‐domain spectroscopy

Abstract

An experimental study on terahertz (THz) magneto‐optical (MO) properties of monolayer (ML) molybdenum disulfide (MoS2) on SiO2/Si substrate is conducted by using THz time‐domain spectroscopy (TDS) in the presence of the magnetic field in the Faraday geometry at liquid nitrogen temperature of 80 K. The complex longitudinal MO conductivity, σxx(ω), is measured for ML MoS2 in different magnetic fields up to 8 T. The real and imaginary parts of σxx(ω) for ML MoS2 depend strongly on the magnetic field and fit well to the generalized MO Drude‐Smith formula. Through fitting the experimental results with the theoretical formula, the key sample and material parameters for ML MoS2 (e.g., the electron density, the electronic relaxation time, the electronic localization factor) are determined magneto‐optically and their dependence upon the magnetic field is examined. It is shown that the presence of the magnetic field can significantly weaken the effect of optically induced electronic backscattering or localization in ML MoS2. This work demonstrates that the MO measurement on the basis of the THz TDS is a powerful experimental technique for the investigation of atomically thin electronic materials and devices such as ML MoS2 on a substrate.

Electronically triggered tunable terahertz signal observed in LPCVD grown single layer graphene

“…This SLG nanosheet conductivity depends on the carrier density and their distribution, unlike semiconductors with parabolic energy bands. 52 In the real part, the negative THz sheet conductivity could be contributed because of the presence of defects in SLG (also supported by Raman spectra in Fig. 1d).…”

New insights into APCVD grown monolayer MoS2 using time-domain terahertz spectroscopy

“…Furthermore, the terahertz time-domain spectroscopy (THz-TDS) has been performed to explore the terahertz characteristics of as deposited monolayer MoS 2 and bulk MoS 2 on sapphire substrate by APCVD technique as shown in Fig. S4 34 . To satisfy the need of highly resistive substrate in order to nullify the conductive losses in substrate 35 for THz-TDS measurements, the sapphire substrate has been chosen for growth of monolayer MoS 2 .…”

Terahertz magneto-optical properties of graphene hydrodynamic electron liquid

“…We predict that the viscosity can also affect the magneto-optical properties of graphene HEL. The viscosity effect in the presence of magnetic field can be probed via THz magneto-optical measurements [23,24]. In this work, we examine the magneto-optical (MO) properties of a graphene-based HEL.…”