Plasma Wave Instabilities in Non-Equilibrium Graphene

Autor: Aryal, Chinta M., Hu, Ben Yu-Kuang, Jauho, Antti-Pekka
Rok vydání: 2015
Předmět:
Zdroj: Phys. Rev. B 94, 115401 (2016)
Druh dokumentu: Working Paper
DOI: 10.1103/PhysRevB.94.115401
Popis: We study two-stream instabilities in a non-equilibrium system in which a stream of electrons is injected into doped graphene. As with equivalent non-equilibrium parabolic band systems, we find that the graphene systems can support unstable charge-density waves whose amplitudes grow with time. We determine the range of wavevector $\boldsymbol{q}$ that are unstable, and their growth rates. We find no instability for waves with wavevectors parallel or perpendicular to the direction of the injected carriers. We find that, within the small wavevector approximation, the angle between $\boldsymbol{q}$ and the direction of the injected electrons that maximizes the growth rate increases with increasing $\boldsymbol{|q|}$. We compare the range and strength of the instability in graphene to that of two and three dimensional parabolic band systems.
Comment: 21 pages, 7 figures
Databáze: arXiv