Continuous-wave operation of λ=3.25 μm broadened-waveguide W quantum-well diode lasers up to T=195 K

Abstract

Mid-infrared (λ=3.25 μm) broadened-waveguide diode lasers with active regions consisting of 5 type-II “W” quantum wells operated in continuous-wave (cw) mode up to 195 K. At 78 K, the threshold current density was 63 A/cm2, and up to 140 mW of cw output power was generated. A second structure with ten quantum wells operated up to 310 K in pulsed mode.

Continuous Wave Operation of a Mid-Infrared Semiconductor Laser at Room Temperature

“…Especially when compared to the visible or near-infrared spectral range, where interband semiconductor lasers are now produced very economically with continuous wave (CW) output power of tens of milliwatts, this assertion holds true. In the mid-infrared, a new class of semiconductor lasers-intersubband quantum cascade (QC) lasers (1)-has become a promising alternative to interband diode lasers (2,3) in the past 7 years. In these devices, photon emission is obtained by electrons making optical transitions between confined energy lev-els.…”

Thermal conductivity of AlAs0.07Sb0.93 and Al0.9Ga0.1As0.07Sb0.93 alloys and (AlAs)1/(AlSb)11 digital-alloy superlattices

“…[1][2][3][4][5][6][7][8] Besides the binaries GaSb, InAs, and AlSb, this family includes a number of ternary (Ga 1Ϫx In x Sb, AlAs x Sb 1Ϫx , etc.͒ and quaternary (Ga 1Ϫx In x As y Sb 1Ϫy , Al x Ga 1Ϫx As y Sb 1Ϫy , etc.͒ random alloys, 9 as well as superlattices ͑e.g., InAs/ AlSb, InAs/Ga 1Ϫx In x Sb) and digital alloys ͑e.g., Ga 1Ϫx In x As/Ga 1Ϫx In x Sb, AlAs/AlSb͒ that provide numerous additional opportunities for engineering of the band structures and electronic wave functions.…”

“…19 The implication is that such layers, which have been employed frequently in the injection regions of antimonide mid-infrared lasers, 27,28 should be avoided from the thermal management standpoint. Since ternary AlAs x Sb 1Ϫx or quaternary Al x Ga 1Ϫx As y Sb 1Ϫy can provide alternative injection regions, 4 it is important to determine the thermal conductivity for those alloys. A second configuration of interest is the ''digital alloy'' 29,30 , in which a͒ Author to whom correspondence should be addressed; electronic mail: borcat@rpi.edu constituent layers may be as thin as 1 monolayer ͑ML͒.…”

Optical and Structural Properties of InAs/GaSb Nanostructures

“…The bandgap (and dispersion) of the superlattice is controlled by the thickness of the InAs and GaSb layers, and the composition of the interfaces. The additional properties of reduced Auger recombination and tunneling rates relative to other material systems with comparable bandgaps have resulted in great interest in the InAs/GaSb system for applications as lasers and detectors from the mid to very long-wave IR [1][2][3][4][5][6][7] . Much investigation, however, is needed on basic materials issues, such as anion intermixing, interfacial roughness, as well as phenomena leading to the structural instability which is the subject of the present study, described below.…”