Abstract-Magnetopolaron effect on shallow-impurity states in the presence of magnetic and intense terahertz laser fields in the Faraday configuration

Weiyang Wang, B. Van Duppen, M. Van der Donck, and F. M. Peeters

https://journals.aps.org/prb/accepted/6d07dO43Z4211c3b81984d103a35761924e4abf57

The magnetopolaron effect on shallow-impurity states in semiconductors is investigated when subjected simultaneously to a magnetic field and an intense terahertz laser field within the Faraday configuration. We use a time-dependent non-perturbative theory to describe electron interactions. The externally applied fields are exactly included via a laser-dressed interaction potential. Through a variational approach we evaluate the binding energy of the shallow-impurity states. We find that the interaction strength of the laser-dressed Coulomb potential can not only be enhanced but also weakened by varying the two external fields. In this way the binding energy can be tuned by the external fields and red- or blue-shifted with respect to the static binding energy. In the nonresonant polaron region, a novel magnetopolaron correction that includes the effects of photon process is observed. In the resonant polaron region, moreover, the resonant {\color{black}magnetopolaron} effect accompanied by the emission and absorption of a single photon is distinctly observed. This can be modulated to be far away from the reststrahlen band. The intriguing findings of this manuscript can be observed experimentally and, in turn, provide a new way to measure the strength of the electron-phonon interaction.

Abstract-Infrared to terahertz optical conductivity of n-type and p-type monolayer MoS2 in the presence of Rashba spin-orbit coupling

Y. M. Xiao, W. Xu, B. Van Duppen, and F. M. Peeters

https://journals.aps.org/prb/abstract/10.1103/PhysRevB.94.155432

We investigate the effect of Rashba spin-orbit coupling (SOC) on the optoelectronic properties of n- and p-type monolayer MoS2. The optical conductivity is calculated within the Kubo formalism. We find that the spin-flip transitions enabled by the Rashba SOC result in a wide absorption window in the optical spectrum. Furthermore, we evaluate the effects of the polarization direction of the radiation, temperature, carrier density, and the strength of the Rashba spin-orbit parameter on the optical conductivity. We find that the position, width, and shape of the absorption peak or absorption window can be tuned by varying these parameters. This study shows that monolayer MoS2 can be a promising tunable optical and optoelectronic material that is active in the infrared to terahertz spectral range.

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Abstract-Infrared to terahertz optical conductivity of n-type and p-type monolayer MoS2 in the presence of Rashba spin-orbit coupling

Y. M. Xiao, W. Xu, B. Van Duppen, and F. M. Peeters

https://journals.aps.org/prb/accepted/3e071OaeHf11f739613c9c781af192427469d99cc

We investigate the effect of Rashba spin-orbit coupling (SOC) on the optoelectronic properties of n- and p-type monolayer MoS2. The optical conductivity is calculated within the Kubo formalism. We find that the spin-flip transitions enabled by the Rashba SOC result in a wide absorption window in the optical spectrum. Furthermore, we evaluate the effects of the polarization direction of the radiation, temperature, carrier density and the strength of the Rashba spin-orbit parameter on the optical conductivity. We find that the position, width, and shape of the absorption peak or absorption window can be tuned by varying these parameters. This study shows that monolayer MoS2 can be a promising tunable optical and optoelectronic material that is active in the infrared to terahertz spectral range.