TY - JOUR
T1 - High-performance quantum cascade lasers
T2 - optimized design through waveguide and thermal modeling
AU - Howard, Scott S.
AU - Liu, Zhijun
AU - Wasserman, Daniel
AU - Hoffman, Anthony J.
AU - Ko, Tiffany S.
AU - Gmachl, Claire F.
N1 - Funding Information:
Manuscript received October 1, 2006; revised August 1, 2007. This work was supported in part by the DARPA Laser-induced Photoacoustic Spectroscopy Program, in part by the Department of Energy, in part by the NSF Engineering Research Center for Mid-InfraRed Technologies for Health and the Environment under Grant EEC-0540832, and in part by the NSF Materials Research Science and Engineering Center under Grant DMR-0216706.
PY - 2007/9
Y1 - 2007/9
N2 - We present a comprehensive model to study the thermal effects in quantum cascade (QC) lasers for continuous-wave (CW) operation at and above room temperature. This model self-consistently solves the temperature-dependent threshold current density equation and heat equation to determine the CW threshold current density, maximum heat sink temperature, and core temperature at threshold for a given laser design. The model includes effects from temperature dependence on thermal backfilling, thermal conductivity, phonon lifetimes, gain bandwidth, thermionic emission, and resistive heating in waveguide layers. Studies on these effects yield results not simultaneously considered by previous models. By including these results in laser designs, lasers with lower core temperatures, with higher operating temperatures, and requiring lower electrical power than current high-performance lasers are predicted. Additionally, experimental results are presented, exploring various methods of improving CW laser performance for a λ∼8 μm QC laser and are compared to the model.
AB - We present a comprehensive model to study the thermal effects in quantum cascade (QC) lasers for continuous-wave (CW) operation at and above room temperature. This model self-consistently solves the temperature-dependent threshold current density equation and heat equation to determine the CW threshold current density, maximum heat sink temperature, and core temperature at threshold for a given laser design. The model includes effects from temperature dependence on thermal backfilling, thermal conductivity, phonon lifetimes, gain bandwidth, thermionic emission, and resistive heating in waveguide layers. Studies on these effects yield results not simultaneously considered by previous models. By including these results in laser designs, lasers with lower core temperatures, with higher operating temperatures, and requiring lower electrical power than current high-performance lasers are predicted. Additionally, experimental results are presented, exploring various methods of improving CW laser performance for a λ∼8 μm QC laser and are compared to the model.
KW - High performance
KW - Quantum cascade (QC) laser
KW - Semiconductor laser
KW - Thermal modeling
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U2 - 10.1109/JSTQE.2007.906121
DO - 10.1109/JSTQE.2007.906121
M3 - Article
AN - SCOPUS:35348930014
SN - 1077-260X
VL - 13
SP - 1054
EP - 1064
JO - IEEE Journal on Selected Topics in Quantum Electronics
JF - IEEE Journal on Selected Topics in Quantum Electronics
IS - 5
ER -