Programme

P.58 -- Posters, VCTP-51

Date: Thursday, 6 August 2026

Time: 09:30 - 10:30

TWO-DIMENSIONAL GRAPHENE: MAGNETO-OPTICAL PHONON RESONANCE IN HALL COEFFICIENT UNDER TERAHERTZ RADIATION

Nguyen Thu Huong (1), Nguyen Quang Son (1,2,*), Nguyen Quang Bau (2), Nguyen Thi Nguyet Anh (2), Vu Tuyet Mai (2), Anh-Tuan Tran (2)

(1) Faculty of Basic Science, Air Defence-Air Force Academy, Doai Phuong, Hanoi 100000, Vietnam. (2) Department of Theoretical Physics, Faculty of Physics, VNU University of Science, Vietnam National University, Hanoi 100000, Vietnam.

This work presents a theoretical investigation of magneto-optical phonon resonance in the Hall effect of two-dimensional graphene subjected to a terahertz laser field. The study is performed within the quantum kinetic equation formalism, considering electron–optical phonon scattering as the dominant interaction mechanism. By solving the quantum kinetic equation for the electron distribution function, analytical expressions for the electrical conductivity tensor and the Hall coefficient are derived as functions of the external magnetic field, laser frequency, and radiation amplitude. Numerical calculations for graphene reveal pronounced magnetophonon resonance peaks in the dependence of the Hall coefficient on the cyclotron energy. These resonance peaks arise when the magneto-phonon-photon resonance condition is satisfied. Their positions are determined solely by the resonance condition and therefore remain unchanged with temperature, leading to an overlap of the resonance peaks obtained at different temperatures. In contrast, the resonance amplitude exhibits a clear temperature dependence. Furthermore, increasing the amplitude of the terahertz radiation results in a reduction of the Hall coefficient. The obtained results provide insights into the interplay among magnetic fields, optical phonons, and electromagnetic radiation in graphene, and may serve as a useful reference for future experimental studies of terahertz-driven transport phenomena.

Presenter: Nguyen Quang Son