skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.


Title: Long wavelength interband cascade lasers
InAs-based interband cascade lasers (ICLs) can be more easily adapted toward long wavelength operation than their GaSb counterparts. Devices made from two recent ICL wafers with an advanced waveguide structure are reported, which demonstrate improved device performance in terms of reduced threshold current densities for ICLs near 11  μm or extended operating wavelength beyond 13  μm. The ICLs near 11  μm yielded a significantly reduced continuous wave (cw) lasing threshold of 23 A/cm2at 80 K with substantially increased cw output power, compared with previously reported ICLs at similar wavelengths. ICLs made from the second wafer incorporated an innovative quantum well active region, comprised of InAsP layers, and lased in the pulsed-mode up to 120 K at 13.2  μm, which is the longest wavelength achieved for III–V interband lasers.  more » « less
Award ID(s):
1931193
PAR ID:
10363582
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
American Institute of Physics
Date Published:
Journal Name:
Applied Physics Letters
Volume:
120
Issue:
9
ISSN:
0003-6951
Page Range / eLocation ID:
Article No. 091105
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. We report significant improvements in threshold current density and maximum operating temperature in continuous wave (CW) operation of interband cascade lasers (ICLs) near 5 μm. The uncoated ICLs were demonstrated at room temperature with a threshold current density of 343.8 A/cm2 and an output power of 31 mW/facet at 25 °C in CW mode. Different ICLs made from the same wafer were compared to study the impact of device dimensions on performance. The threshold current density of 331 A/cm2 achieved from a facet-uncoated 5 mm-long device at 25 °C is the lowest among all previously reported room temperature CW ICLs with emission wavelengths longer than 4 μm. Compared to the previous record of 480 A/cm2 at 4.75 μm for a facet-coated 4-mm-long ICL at 25 °C, this value of 331 A/cm2 is reduced by 31%, representing a substantial improvement. Benefited from improved device fabrication and enhanced thermal dissipation, the maximum CW operating temperature of the device reached 66 °C, which is the highest ever reported for ICLs with similar emission wavelengths. 
    more » « less
  2. We report the demonstration of continuous-wave interband cascade lasers (ICLs) near 13 μm. The attained lasing wavelength of 13.2 μm at 92 K stands as the longest cw emission wavelength ever reported for III-V interband lasers. This achievement is attributed to the adoption of an innovative quantum well (QW) active region comprising strained InAs0.5P0.5 layers in contrast to the commonly used “W” QW active region, showing the potential of the modified QW active region with InAsP layers in improving device performance and extending wavelength coverage of ICLs. 
    more » « less
  3. We report on the substantial advancement of long wavelength InAs-based interband cascade lasers (ICLs) utilizing advanced waveguides formed from hybrid cladding layers and targeting the 10-12 μm wavelength region. Modifications in the hole injector have improved carrier transport in these ICLs, resulting in significantly reduced threshold voltages (Vth) as low as 3.62 V at 80 K. Consequently, much higher voltage efficiencies were observed, peaking at about 73% at 10.3 μm and allowing for large output powers of more than 100 mW/facet. Also, low threshold current densities (Jth) of 8.8 A/cm2 in cw mode and 7.6 A/cm2 in pulsed mode near 10 μm were observed; a result of adjustments in the GaInSb hole well composition intended to reduce the overall strain accumulation in the ICL. Furthermore, an ICL from the second wafer operating at a longer wavelength achieved a peak voltage efficiency of 57% at 11.7 μm, with a peak output power of more than 27 mW/facet. This ICL went on to lase beyond 12 μm in both cw and pulsed modes, representing a new milestone in long wavelength coverage for ICLs with the standard W-QW active region. 
    more » « less
  4. We report significantly enhanced device performance in long wavelength interband cascade lasers (ICLs) by employing a recently proposed innovative quantum well (QW) active region containing strained InAsP layers. These ICLs were able to operate at wavelengths near 14.4 μm, the longest ever demonstrated for III–V interband lasers, implying great potential of ICLs to cover an even wider wavelength range. Also, by applying the aforesaid QW active region configuration on ICLs at relatively short wavelengths, ICLs were demonstrated at a low threshold current density (e.g., 13 A/cm2 at 80 K) and at temperatures up to 212 K near 12.4 μm, more than 50 K higher than the previously reported ICLs with the standard W-shape QW active region at similar wavelengths. This suggests that the QW active region with InAsP layers can be used to improve device performance at the shorter wavelengths. 
    more » « less
  5. Abstract Interband cascade lasers (ICLs) based on the type-II quantum well (QW) active region have attracted much attention for a range of practical applications in the mid-infrared due, in part, to their low power consumption. However, extending the operating wavelength of these ICLs into the long-wave infrared region presents several challenges including the reduced thermal conductivity of the optical cladding layers and the diminished wavefunction overlap in the type-II QW. One solution to alleviate the former concern is to use InAs-based ICLs. To solve the latter problem, InAs 0.5 P 0.5 barriers are introduced in the active region, which lowers the electronic energy level and allows for the InAs well width to be reduced at longer emission wavelengths. Here the advancement of long wavelength ICLs, made from four new InAs-based ICL wafers grown by molecular beam epitaxy, is reported. These ICLs lased in the wavelength range from 10 to 13 µ m and showed significantly improved performance compared with previous ICLs, including the first demonstration of broad-area devices operating in continuous wave mode beyond 12 µ m. These ICLs exhibited substantially increased output powers with reduced threshold voltages ( V th ) and current densities ( J th ). They operated at temperatures up to 40 K higher than previous ICLs at similar wavelengths. 
    more » « less