Title :
Pulsed and continuous-wave operation of long wavelength infrared (λ=9.3 μm) quantum cascade lasers
Author :
Sirtori, Carlo ; Faist, Jerome ; Capasso, Federico ; Sivco, Deborah L. ; Hutchinson, Albert L. ; Cho, Alfred Y.
Author_Institution :
Bell Lab., Lucent Technol., Murray Hill, NJ, USA
fDate :
1/1/1997 12:00:00 AM
Abstract :
The operation of quantum cascade lasers at a wavelength (λ≃9.3 μm) well within the 8-13-μm atmospheric window is reported. A detailed study of intersubband luminescence in a vertical transition structure shows linewidths as narrow as ~10 meV at cryogenic temperatures, increasing to 20 meV at room temperature. Pulsed operation is demonstrated up to 220 K with a peak power ≈10 mW and ≈35 mW at 140 K. The temperature dependence of the threshold current density (J th) is described by a high T0 (128 K), Jth is also systematically studied as a function of cavity length to determine the peak gain and waveguide losses. Continuous-wave, single-mode operation is demonstrated up to 30 K with powers ≈2 mW
Keywords :
cryogenics; current density; infrared sources; laser cavity resonators; laser modes; laser transitions; optical losses; photoluminescence; quantum well lasers; spectral line breadth; waveguide lasers; μm atmospheric window; 10 mW; 10 meV; 128 K; 140 K; 2 mW; 220 K; 30 K; 35 mW; 8 to 13 mum; 9.3 mum; cavity length; continuous-wave operation; cryogenic temperatures; intersubband luminescence; long wavelength infrared quantum cascade lasers; peak gain; peak power; pulsed operation; room temperature; single-mode operation; temperature dependence; threshold current density; vertical transition structure; waveguide losses; Atmospheric waves; Electrons; Laser transitions; Optical pulses; Optical scattering; Quantum cascade lasers; Resonance; Semiconductor lasers; Temperature; Waveguide lasers;
Journal_Title :
Quantum Electronics, IEEE Journal of
