Sb-Based Mid-Infrared Diode Lasers
Abstract:
In this paper we review recent progress achieved in our development of type-1 GaInAsSbAlGaAsSb quantum-well QW lasers with emission wavelength in the 1.74 - 2.34 micrometers range. Triple-QW 3-QW and single-QW SQW diode lasers having broadened waveguide design emitting around 2.26 micrometers have been studied in particular. Comparing the two designs we have find that the threshold current density at infinite cavity length as well as the transparency current density scale with the number of QWs. Maximum cw operating temperature exceeding 50 deg C and 90 deg C has been obtained for ridge waveguide lasers emitting above and below 2 micrometers, respectively. Ridge waveguide diode lasers emitting at 1.94 micrometers exhibited internal quantum efficiencies in excess of 77, internal losses of 6cm, and threshold current density at infinite cavity length as low as 121 Asq cm reflecting the superior quality of our diode lasers, all values recorded at 280 K. A high characteristic temperature Tsub O of 179 K for the threshold current along with a value of T1 433 K for the characteristic temperature of the external efficiency have been attained for the 250 - 280 K temperature interval. Room temperature cw output powers exceeding 1.7 W have been demonstrated for broad area single element devices with high-reflectionantireflection coated mirror facets, mounted epi-side down. The latter result is a proof for the high power capabilities of these GaSb-based mid-ir diode lasers.