Terahertz light-emitting graphene-channel transistor toward single-mode lasing

Yadav Deepika; Tamamushi Gen; Watanabe Takayuki; Mitsushio Junki; Tobah Youssef; Sugawara Kenta; Dubinov Alexander A.; Satou Akira; Ryzhii Maxim; Ryzhii Victor; Otsuji Taiichi

doi:10.1515/nanoph-2017-0106

Nanophotonics (Mar 2018)

Terahertz light-emitting graphene-channel transistor toward single-mode lasing

Yadav Deepika,
Tamamushi Gen,
Watanabe Takayuki,
Mitsushio Junki,
Tobah Youssef,
Sugawara Kenta,
Dubinov Alexander A.,
Satou Akira,
Ryzhii Maxim,
Ryzhii Victor,
Otsuji Taiichi

Affiliations

Yadav Deepika: Research Institute of Electrical Communication, Tohoku University, Sendai 9808577, Japan
Tamamushi Gen: Research Institute of Electrical Communication, Tohoku University, Sendai 9808577, Japan
Watanabe Takayuki: Research Institute of Electrical Communication, Tohoku University, Sendai 9808577, Japan
Mitsushio Junki: Research Institute of Electrical Communication, Tohoku University, Sendai 9808577, Japan
Tobah Youssef: Department of Electrical and Computer Engineering, University of Texas at Austin, Austin 78712, TX, USA
Sugawara Kenta: Research Institute of Electrical Communication, Tohoku University, Sendai 9808577, Japan
Dubinov Alexander A.: Institute for Physics of Microstructures, Russian Academy of Sciences, Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod 603950, Russia
Satou Akira: Research Institute of Electrical Communication, Tohoku University, Sendai 9808577, Japan
Ryzhii Maxim: Department of Computer Science and Engineering, University of Aizu, Aizu-Wakamatsu 965-8580, Japan
Ryzhii Victor: Research Institute of Electrical Communication, Tohoku University, Sendai 9808577, Japan
Otsuji Taiichi: Research Institute of Electrical Communication, Tohoku University, Sendai 9808577, Japan

DOI: https://doi.org/10.1515/nanoph-2017-0106
Journal volume & issue: Vol. 7, no. 4
pp. 741 – 752

Abstract

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A distributed feedback dual-gate graphene-channel field-effect transistor (DFB-DG-GFET) was fabricated as a current-injection terahertz (THz) light-emitting laser transistor. We observed a broadband emission in a 1–7.6-THz range with a maximum radiation power of ~10 μW as well as a single-mode emission at 5.2 THz with a radiation power of ~0.1 μW both at 100 K when the carrier injection stays between the lower cutoff and upper cutoff threshold levels. The device also exhibited peculiar nonlinear threshold-like behavior with respect to the current-injection level. The LED-like broadband emission is interpreted as an amplified spontaneous THz emission being transcended to a single-mode lasing. Design constraints on waveguide structures for better THz photon field confinement with higher gain overlapping as well as DFB cavity structures with higher Q factors are also addressed towards intense, single-mode continuous wave THz lasing at room temperature.

Published in Nanophotonics

ISSN: 2192-8606 (Print); 2192-8614 (Online)
Publisher: De Gruyter
Country of publisher: Germany
LCC subjects: Science: Physics
Website: https://www.degruyter.com/journal/key/nanoph/html#submit

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