Open AccessSix-level hybrid extraction/injection scheme terahertz quantum cascade laser with suppressed thermally activated carrier leakage
Author(s) -
Boyu Wen,
Chris Deimert,
Siyi Wang,
Chao Xu,
SM Shazzad Rassel,
Z. R. Wasilewski,
Dayan Ban
Publication year - 2020
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.400246
Subject(s) - quantum cascade laser , terahertz radiation , materials science , lasing threshold , cascade , leakage (economics) , optoelectronics , laser , optics , excited state , scattering , physics , atomic physics , chemistry , wavelength , chromatography , economics , macroeconomics
This work presents a six-level scheme terahertz (THz) quantum cascade laser (QCL) design in which the resonant-phonon (RP) and the scattering-assisted (SA) injection/extraction are combined within a single Al 0.15 Ga 0.85 As/GaAs based structure. By utilizing extra excited states for hybrid extraction/injection channels, this design minimizes the appearance of an intermediate negative differential resistance (NDR) before the lasing threshold. The final negative differential resistance is observed up to 260K and a high characteristic temperature of 259 K is measured. These observations imply very effective suppression of pre-threshold electrical instability and thermally activated leakage current. In addition, the impact of critical design parameters of this scheme is investigated.