TITLE:
Amplification of Terahertz Optical Phonons and Plasmons by 2D Electron Drift in the Structures Graphene-Semiconductor and in Heterostructures
AUTHORS:
Volodymyr Grimalsky, Margarita Tecpoyotl-Torres, Yuriy Rapoport, Oskar Nava-Fuerte
KEYWORDS:
Graphene, Nitride Semiconductors, 2D Electron Drift, Terahertz Hybrid Waves, Instability
JOURNAL NAME:
Journal of Electromagnetic Analysis and Applications,
Vol.18 No.11,
November
3,
2026
ABSTRACT: Generation and amplification of terahertz oscillations is investigated theoretically in structures graphene-semiconductor layers. The instability of hybrid space charge waves in graphene-optical phonons or plasmons in semiconductor layers is of Cherenkov type. It can be realized when the drift velocity of 2D electron gas in graphene exceeds some critical value. The numerical simulations of instability are based on the quantum kinetic approach. The main obstacle of implementing the specified instability is the heating of 2D electron gas during its drift. Therefore, the investigations are performed for moderately low temperatures T ≤ 200 K, and the electron gas is degenerated. The best results are obtained for the structures with nitride semiconductors GaN, InN, A comparison with the drift instability in semiconductor heterostructures with 2D electron gas is given too, where the increments of instability are comparable.