Negative terahertz conductivity in remotely doped graphene bilayer heterostructures

Journal Article · Sat Nov 14 04:00:00 EST 2015 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4934856· OSTI ID:22492903

Ryzhii, V. ^[1]; Ryzhii, M. ^[2]; Mitin, V. ^[3]; Shur, M. S. ^[4]; Otsuji, T. ^[1]

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1. Research Institute of Electrical Communication, Tohoku University, Sendai 980-8577 (Japan)
2. Department of Computer Science and Engineering, University of Aizu, Aizu-Wakamatsu 965-8580 (Japan)
3. Department of Electrical Engineering, University at Buffalo, SUNY, Buffalo, New York 1460-1920 (United States)
4. Departments of Electrical, Electronics, and Systems Engineering and Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States)

Injection or optical generation of electrons and holes in graphene bilayers (GBLs) can result in the interband population inversion enabling the terahertz (THz) radiation lasing. The intraband radiative processes compete with the interband transitions. We demonstrate that remote doping enhances the indirect interband generation of photons in the proposed GBL heterostructures. Therefore, such remote doping helps to surpass the intraband (Drude) absorption, and results in large absolute values of the negative dynamic THz conductivity in a wide range of frequencies at elevated (including room) temperatures. The remotely doped GBL heterostructure THz lasers are expected to achieve higher THz gain compared with previously proposed GBL-based THz lasers.

• OSTI ID: 22492903
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 18 Vol. 118; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ABSORPTION
DOPED MATERIALS
ENERGY-LEVEL TRANSITIONS
GRAPHENE
HOLES
LASERS
LAYERS
PHOTONS
POPULATION INVERSION
TEMPERATURE RANGE 0273-0400 K