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Title: Terahertz graphene lasers: Injection versus optical pumping

Journal Article · · AIP Conference Proceedings
DOI:https://doi.org/10.1063/1.4848313· OSTI ID:22261753
;  [1];  [2];  [3]
  1. Research Institute for Electrical Communication, Tohoku University, Sendai 980-8577 (Japan)
  2. Computational Nanoelectronics Laboratory, University of Aizu, Aizu-Wakamatsu 965-8580 (Japan)
  3. Department of Electrical Engineering, University at Buffalo, SUNY, Buffalo, New York 14260-1920 (United States)

We analyze the formation of nonequilibrium states in optically pumped graphene layers and in forward-biased graphene structures with lateral p-i-n junctions and consider the conditions of population inversion and lasing. The model used accounts for intraband and interband relaxation processes as well as deviation of the optical phonon system from equilibrium. As shown, optical pumping suffers from a significant heating of both the electron-hole plasma and the optical phonon system, which can suppress the formation of population inversion. In the graphene structures with p-i-n junction, the injected electrons and holes have relatively low energies, so that the effect of cooling can be rather pronounced, providing a significant advantage of the injection pumping in realization of graphene terahertz lasers.

OSTI ID:
22261753
Journal Information:
AIP Conference Proceedings, Vol. 1566, Issue 1; Conference: ICPS 2012: 31. international conference on the physics of semiconductors, Zurich (Switzerland), 29 Jul - 3 Aug 2012; Other Information: (c) 2013 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
Country of Publication:
United States
Language:
English