Open AccessTemperature-insensitive long-wavelength (λ ≈14 µm) Quantum Cascade lasers with low threshold
Author(s) -
Xinyue Huang,
William Charles,
Claire F. Gmachl
Publication year - 2011
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.19.008297
Subject(s) - cascade , laser , optics , wavelength , physics , quantum cascade laser , scattering , slope efficiency , materials science , atomic physics , optoelectronics , fiber laser , chemistry , chromatography
We demonstrate high-performance, long-wavelength (λ ≈14 µm) Quantum Cascade (QC) lasers based on a diagonal optical transition and a "two-phonon-continuum" depletion scheme in which the lower laser level is depopulated by resonant longitudinal optical phonon scattering followed by scattering to a lower energy level continuum. A 2.8 mm long QC laser shows a low threshold current density of 2.0 kA/cm2, a peak output power of ~336 mW, and a slope efficiency of 375 mW/A, all at 300 K, with a high characteristic temperature T0 ~310 K over a wide temperature range from 240 K to 390 K.