Center for Quantum Devices - Most Downloaded Journal Articles

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19.	Gas sensing spectroscopy system utilizing a sample grating distributed feedback quantum cascade laser array and type II superlattice detector Nathaniel R. Coirier; Andrea I. Gomez-Patron; Manijeh Razeghi Proc. SPIE 11288, Quantum Sensing and Nano Electronics and Photonics XVII, 1128815-- January 31, 2020 ...[Visit Journal] Gas spectroscopy is a tool that can be used in a variety of applications. One example is in the medical field, where it can diagnose patients by detecting biomarkers in breath, and another is in the security field, where it can safely alert personnel about ambient concentrations of dangerous gas. In this paper, we document the design and construction of a system compact enough to be easily deployable in defense, healthcare, and chemical safety environments. Current gas sensing systems use basic quantum cascade lasers (QCLs) or distributed feedback quantum cascade lasers (DFB QCLs) with large benchtop signal recovery systems to determine gas concentrations. There are significant issues with these setups, namely the lack of laser tunability and the lack of practicality outside of a very clean lab setting. QCLs are advantageous for gas sensing purposes because they are the most efficient lasers at the mid infrared region (MIR). This is necessary since gases tend to have stronger absorption lines in the MIR range than in the near-infrared (NIR) region. To incorporate the efficiency of a QCL with wide tuning capabilities in the MIR region, sampled grating distributed feedback (SGDFB) QCLs are the answer as they have produced systems that are widely tunable, which is advantageous for scanning a robust and complete absorption spectrum. The system employs a SGDFB QCL array emitter, a Type II InAsSb Superlattice detector receiver, a gas cell, and a cooling system. [reprint (PDF)]
19.	High Detectivity GaInAs/InP Quantum Well Infrared Photodetectors Grown on Si Substrates J. Jiang, C. Jelen, M. Razeghi and G.J. Brown IEEE Photonics Technology Letters 14 (3)-- March 1, 2002 ...[Visit Journal] In this letter, we report an improvement in the growth and the device performance of GaInAs-InP quantum well infrared photodetectors grown on Si substrates. Material growth techniques, like low-temperature nucleation layers and thick buffer layers were used to grow InP on Si. An in situ thermal cycle annealing technique was used to reduce the threading dislocation density in the InP-on-Si. Detector dark current was reduced 2 orders of magnitude by this method. Record high detectivity of 2.3 × 10⁹ cm·Hz^½·W^-1 was obtained for QWIP-on-Si detectors in the 7-9 μm range at 77 K [reprint (PDF)]
19.	Room temperature continuous wave operation of quantum cascade lasers with watt-level optical power Y. Bai, S.R. Darvish, S. Slivken, W. Zhang, A. Evans, J. Nguyen and M. Razeghi Applied Physics Letters, Vol. 92, No. 10, p. 101105-1-- March 10, 2008 ...[Visit Journal] We demonstrate quantum cascade lasers at an emitting wavelength of 4.6 µm, which are capable of room temperature, high power continuous wave (cw) operation. Buried ridge geometry with a width of 9.8 µm was utilized. A device with a 3 mm cavity length that was epilayer-down bonded on a diamond submount exhibited a maximum output power of 1.3 W at room temperature in cw operation. The maximum output power at 80 K was measured to be 4 W, with a wall plug efficiency of 27%. [reprint (PDF)]
19.	High Thermal Stability of κ-Ga2O3 Grown by MOCVD Junhee Lee, Honghyuk Kim, Lakshay Gautam and Manijeh Razeghi Lee, J.; Kim, H.; Gautam, L.; Razeghi, M. High Thermal Stability of κ-Ga2O3 Grown by MOCVD. Crystals 2021, 11, 446. https://doi.org/ 10.3390/cryst11040446 ...[Visit Journal] We report a high thermal stability of kappa gallium oxide grown on c-plane sapphire substrate by metal organic chemical vapor deposition. Kappa gallium oxide is widely known as a metastable polymorph transitioning its phase when subjected to a high temperature. Here, we show the kappa gallium oxide whose phase is stable in a high temperature annealing process at 1000 °C. These oxide films were grown at 690 °C under nitrogen carrier gas. The materials showed high electrical resistivity when doped with silicon, whereas the film conductivity was significantly improved when doped with both indium and silicon. This work provides a pathway to overcoming limitations for the advance in utilizing kappa gallium oxide possessing superior electrical characteristics. [reprint (PDF)]
19.	Molecular Beam Epitaxial Growth of High Quality InSb for p-i-n Photodetectors G. Singh, E. Michel, C. Jelen, S. Slivken, J. Xu, P. Bove, I. Ferguson, and M. Razeghi Journal of Vacuum Science and Technology B, 13 (2)-- March 1, 1995 ...[Visit Journal] The InSb infrared photodetectors grown heteroepitaxially on Si substrates by molecular beam epitaxy (MBE) are reported. Excellent InSb material quality is obtained on 3-inch Si substrates (with a GaAs predeposition) as confirmed by structural, optical, and electrical analysis. InSb infrared photodetectors on Si substrates that can operate from 77 K to room temperature have been demonstrated. The peak voltage-responsitivity at 4 μm is about 1.0×10³ V/W and the corresponding Johnson-noise-limited detectivity is calculated to be 2.8×10¹⁰ cm·Hz^½/W. This is the first important stage in developing InSb detector arrays or monolithic focal plane arrays (FPAs) on silicon. The development of this technology could provide a challenge to traditional hybrid FPA's in the future. [reprint (PDF)]
19.	Improved performance of IR photodetectors with 3D gap engineering J. Piotrowski and M. Razeghi Optoelectronic Integrated Circuit Materials, Physics and Devices, SPIE Conference, San Jose, CA; Proceedings, Vol. 2397-- February 6, 1995 ...[Visit Journal] The ultimate signal-to-noise performance of the semiconductor photodetector is limited by the statistical fluctuations of the thermal generation and recombination rates in photodetector material. Cooling is an effective but impractical way of suppression of the thermal processes. The performance of uncooled detectors can be improved by minimizing the thermal generation and recombination rates and reducing the actual volume of photodetector. This can be realized in 3D heterostructure devices. In these devices, the incident radiation is absorbed in small regions of narrow gap semiconductor, buried in wide gap volume and supplied with wide gap electric contacts and radiation concentrators. The practical near room-temperature 1 - 12 μm IR heterostructure photodetectors are reported. The devices are based on variable gap Hg_1-xCd_xTe. The 3D heterostructures have been obtained by Isothermal Vapor Growth Epitaxy in a reusable growth system which enables in situ doping during growth with foreign impurities. Ion milling was extensively used in preparation of the devices. Monolithic optical immersion has been applied for further improvement of performance. The 3D heterostructure devices exhibit performance exceeding that of conventional photodetectors. [reprint (PDF)]
19.	Sb-based infrared materials and photodetectors for the near room temperature applications J.D. Kim, E. Michel, H. Mohseni, J. Wojkowski, J.J. Lee and M. Razeghi SPIE Conference, San Jose, CA, Vol. 2999, pp. 55-- February 12, 1997 ...[Visit Journal] We report on the growth of InSb, InAsSb, and InTlSb alloys for infrared photodetector applications. The fabrication and characterization of photodetectors based on these materials are also reported. Both photoconductive and photovoltaic devices are investigated. The materials and detector structures were grown on (100) and (111)B semi-insulating GaAs and GaAs coated Si substrates by low pressure metalorganic chemical vapor deposition and solid source molecular beam epitaxy. Photoconductive detectors fabricated from InAsSb and InTlSb have been operated in the temperature range from 77 K to 300 K. The material parameters for photovoltaic device structures have been optimized through theoretical calculations based on fundamental mechanisms. InSb p-i-n photodiodes with 77 K peak responsivities approximately 103 V/W were grown on Si and (111) GaAs substrates. An InAsSb photovoltaic detector with a composition of x equals 0.85 showed photoresponse up to 13 micrometers at 300 K with a peak responsivity of 9.13 X 10-2 V/W at 8 micrometers . The RoA product of InAsSb detectors has been theoretically and experimentally analyzed. [reprint (PDF)]
19.	Growth of Deep UV Light Emitting Diodes by Metalorganic Chemical Vapor Deposition A. Yasan, R. McClintock, K. Mayes, D. Shiell, S. Darvish, P. Kung and M. Razeghi SPIE Conference, Jose, CA, Vol. 5359, pp. 400-- January 25, 2004 ...[Visit Journal] We demonstrate high power AlGaN based ultraviolet light-emitting diodes (UV LEDs) with an emission wavelength of 280 nm using an asymmetric single quantum well active layer configuration on top of a high-quality AlGaN/AlN template layer grown by metalorganic chemical vapor deposition (MOCVD). An output power of 1.8 mW at a pulsed current of 400 mA was achieved for a single 300 µm × 300 µm diode. This device reached a high peak external quantum efficiency of 0.24% at 40 mA. An array of four diodes produced 6.5 mW at 880 mA of pulsed current. [reprint (PDF)]
19.	Tunability of intersubband absorption from 4.5 to 5.3 µm in a GaN/Al_0.2Ga_0.8N superlattices grown by metalorganic chemical vapor deposition N. Péré-Laperne, C. Bayram, L. Nguyen-Thê, R. McClintock, and M. Razeghi Applied Physics Letters, Vol. 95, No. 13, p. 131109-- September 28, 2009 ...[Visit Journal] Intersubband (ISB) absorption at wavelengths as long as 5.3 µm is realized in GaN/Al_0.2Ga_0.8N superlattices grown by metalorganic chemical vapor deposition. By employing low aluminum content Al_0.2Ga_0.8N barriers and varying the well width from 2.6 to 5.1 nm, ISB absorption has been tuned from 4.5 to 5.3 µm. Theoretical ISB absorption and interband emission models are developed and compared to the experimental results. The effects of band offsets and the piezoelectric fields on these superlattices are investigated. [reprint (PDF)]
19.	Fabrication of Indium Bumps for Hybrid Infrared Focal Plane Array Applications J. Jiang, S. Tsao, T. O'Sullivan, M. Razeghi, and G.J. Brown Infrared Physics and Technology, 45 (2)-- March 1, 2004 ...[Visit Journal] Hybrid infrared focal plane arrays (FPAs) have found many applications. In hybrid IR FPAs, FPA and Si read out integrated circuits (ROICs) are bonded together with indium bumps by flip-chip bonding. Taller and higher uniformity indium bumps are always being pursued in FPA fabrication. In this paper, two indium bump fabrication processes based on evaporation and electroplating techniques are developed. Issues related to each fabrication technique are addressed in detail. The evaporation technique is based on a unique positive lithography process. The electroplating method achieves taller indium bumps with a high aspect ratio by a unique “multi-stack” technique. This technique could potentially benefit the fabrication of multi-color FPAs. Finally, a proposed low-cost indium bump fabrication technique, the “bump transfer”, is given as a future technology for hybrid IR FPA fabrication. [reprint (PDF)]
19.	320x256 infrared focal plane array based on type-II InAs/GaSb superlattice with a 12 μm cutoff wavelength P.Y. Delaunay, B.M. Nguyen, D. Hoffman, and M. Razeghi SPIE Porceedings, Vol. 6542, Orlando, FL 2007, p. 654204-- April 9, 2007 ...[Visit Journal] In the past few years, significant progress has been made in the structure design, growth and processing of Type-II InAs/GaSb superlattice photodetectors. Type-II superlattice demonstrated its ability to perform imaging in the middle and long infra-red range, becoming a potential competitor for technologies such as QWIP and HgCdTe. Using an empirical tight-binding model, we developed a superlattice design that matches the lattice parameter of GaSb substrates and presents a cutoff wavelength of 12 μm. Electrical and optical measurements performed on single element detectors at 77 K showed an R₀A averaging 13 Ω·cm² and a quantum efficiency as high as 54%. We demonstrated high quality material growth with x-ray FWHM below 30 arcsec and an AFM rms roughness of 1.5 Å over an area of 20x20 μm². A 320x256 array of 25x25μm² pixels, hybridized to an Indigo Read Out Integrated Circuit, performed thermal imaging up to 185 K with an operability close to 97%. The noise equivalent temperature difference at 81 K presented a peak at 270 mK, corresponding to a mean value of 340 mK. [reprint (PDF)]
19.	High-power, room-temperature and continuous-wave operation of distributed-feedback quantum-cascade lasers at λ = 4.8 µm J.S. Yu, S. Slivken, S.R. Darvish, A. Evans, B. Gokden and M. Razeghi Virtual Journal of Nanoscale Science and Technology 12 (5)-- August 1, 2005 ...[Visit Journal][reprint (PDF)]
19.	Characteristics of Self-Assembled InGaAs/InGaP Quantum Dot Mid-Infrared Photoconductive Detectors Grown by Low Pressure MOCVD S. Kim, M. Erdtmann, and M. Razeghi SPIE Conference, San Jose, CA, -- January 27, 1999 ...[Visit Journal] We report the first self-assembled InGaAs/InGaP quantum dot intersubband infrared photoconductive detectors (QDIPs) grown on semi-insulating GaAs substrate by low pressure metal organic chemical vapor deposition (MOCVD). The InGaAs quantum dots were constructed on an InGaP matrix as self assembling in Stranski-Krastanow growth mode in optimum growth conditions. The detector structure was prepared for single layer and multi-stacked quantum dots for active region. Normal incident photoconductive response was observed at a peak wavelength of 5.5 μm with a high responsivity of 130 mA/W, and a detectivity of 4.74 X 10⁷ cm·Hz^½/W at 77 K for multi-stack QDIP. Low temperature photoresponse of the single quantum dot photodetector was characterized. Peak response was obtained between 16 K and 60 K. The detailed dark current noise measurements were carried on single and multistack quantum dot infrared detectors. High photoconductive gain as 7.6 x 10³ biased at 0.5 V results in increasing the intersubband carrier relaxation time as two order of magnitude compared quantum well infrared photodetectors. [reprint (PDF)]
19.	Dual section quantum cascade lasers with wide electrical tuning S. Slivken, N. Bandyopadhyay, S. Tsao, S. Nida, Y. Bai, Q.Y. Lu and M. Razeghi SPIE Proceedings, Vol. 8631, p. 86310P-1, Photonics West, San Francisco, CA-- February 3, 2013 ...[Visit Journal] This paper describes our development efforts at Northwestern University regarding dual-section sampled grating distributed feedback (SGDFB) QCLs. These devices are the same size, but have much wider electrical tuning, than a traditional DFB laser. In this paper, I will show how we have dramatically extended the monolithic tuning range of high power quantum cascade lasers with high side mode suppression. This includes individual laser element tuning of up to 50 cm^-1 and 24 dB average side mode suppression. These lasers are capable of room temperature continuous operation with high power (>100 mW) output. Additionally, we have demonstrated a broad spectral coverage of over 350 cm^-1 on a single chip, which is equivalent to 87.5% of the gain bandwidth. The eventual goal is to realize an extended array of such laser modules in order to continuously cover a similar or broader spectral range, similar to an external cavity device without any external components. [reprint (PDF)]
19.	8-13 μm InAsSb heterojunction photodiode operating at near room temperature J.D. Kim, S. Kim, D. Wu, J. Wojkowski, J. Xu, J. Piotrowski, E. Bigan, and M. Razeghi Applied Physics Letters 67 (18)-- October 30, 1995 ...[Visit Journal] p⁺-InSb/π-InAs_1−xSb_x/n⁺-InSb heterojunction photodiodes operating at near room temperature in the 8–13 μm region of infrared (IR) spectrum are reported. A room‐temperature photovoltaic response of up to 13 μm has been observed at 300 K with an x≊0.85 sample. The voltage responsivity‐area product of 3×10⁻⁵ V· cm²/W has been obtained at 300 K for the λ=10.6 μm optimized device. This was close to the theoretical limit set by the Auger mechanism, with a detectivity at room temperature of ≊1.5×10⁸ cm ·Hz^½/W. [reprint (PDF)]
19.	Advanced InAs/GaSb Superlattice Photovoltaic Detectors for Very-Long Wavelength Infrared Applications Y. Wei, A. Gin, M. Razeghi, and G.J. Brown Applied Physics Letters 80 (18)-- May 6, 2002 ...[Visit Journal] We report on the temperature dependence of the photoresponse of very long wavelength infrared type-II InAs/GaSb superlattice based photovoltaic detectors grown by molecular-beam epitaxy. The detectors had a 50% cutoff wavelength of 18.8 μm and a peak current responsivity of 4 A·W^-1 at 80 K. A peak detectivity of 4.5×10¹⁰ cm· Hz^½·W^-1 was achieved at 80 K at a reverse bias of 110 mV. The generation–recombination lifetime was 0.4 ns at 80 K. The cutoff wavelength increased very slowly with increasing temperature with a net shift from 20 to 80 K of only 1.2 μm [reprint (PDF)]
19.	High Power, Room Temperature, Continuous-Wave Operation of Quantum Cascade Lasers Grown by GasMBE A. Evans, J. David, L. Doris, J.S. Yu, S. Slivken and M. Razeghi SPIE Conference, Jose, CA, Vol. 5359, pp. 188-- January 25, 2004 ...[Visit Journal] Very high power continuous-wave quantum cascade lasers are demonstrated in the mid-infrared (3 - 6 µm) wavelength range. λ~6 µm high-reflectivity coated QCLs are demonstrated producing over 370 mW continuous-wave power at room temperature with continuous-wave operation up to 333 K. Advanced heterostructure geometries, including the use of a thick electroplated gold, epilayer-side heat sink and a buried-ridge heterostructure are demonstrated to improve laser performance significantly when combined with narrow laser ridges. Recent significant improvements in CW operation are presented and include the development if narrow (9 µm-wide) ridges for high temperature CW operation. GasMBE growth of the strain-balanced λ~6 µm QCL heterostructure is discussed. X-ray diffraction measurements are presented and compared to computer simulations that indicate excellent layer and compositional uniformity of the structure. [reprint (PDF)]
19.	2.4 W room temperature continuous wave operation of distributed feedback quantum cascade lasers Q.Y. Lu, Y. Bai, N. Bandyopadhyay, S. Slivken and M. Razeghi Applied Physics Letters, Vol. 98, No. 18, p. 181106-1-- May 4, 2011 ...[Visit Journal] We demonstrate high power continuous-wave room-temperature operation surface-grating distributed feedback quantum cascade lasers at 4.8 μm. High power single mode operation benefits from a combination of high-reflection and antireflection coatings. Maximum single-facet continuous-wave output power of 2.4 W and peak wall plug efficiency of 10% from one facet is obtained at 298 K. Single mode operation with a side mode suppression ratio of 30 dB and single-lobed far field without beam steering is observed. [reprint (PDF)]
19.	280 nm UV LEDs Grown on HVPE GaN Substrates A. Yasan, R. McClintock, K. Mayes, S.R. Darvish, P. Kung, M. Razeghi, and R.J. Molnar Opto-Electronics Review, 10 (4)-- January 1, 2002 ...[Visit Journal] We report on the enhancement of optical and electrical properties of 280 nm UV LEDs using low dislocation density HVPE-grown GaN substrate. Compared with the same structure grown on sapphire, these LEDs show ~30% reduction in current-voltage differential resistance, ~15% reduction in turn-on voltage, more than 200% increase in output power slope efficiency and saturation at higher currents. Lower density of defects due to higher material quality and better heat dissipation are believed to be the reason behind these improvements. [reprint (PDF)]
19.	Development of Quantum Cascade Lasers for High Peak Output Power and Low Threshold Current Density S. Slivken and M. Razeghi Solid State Electronics 46-- January 1, 2002 ...[Visit Journal] Design and material optimization are used to both decrease the threshold current density and increase the output power for quantum cascade lasers. Waveguides are designed to try and minimize free-carrier and surface-plasmon absorption. Excellent material characterization is also presented, showing excellent control over layer thickness, interface quality, and doping level. Experiments are done to both optimize the injector doping level and to maximize the output power from a single aperture. At 300 K, a threshold current density as low as 1.8 kA/cm² is reported, along with peak powers of approximately 2.5 W. Strain-balanced lasers are also demonstrated at λnot, vert, similar5 μm, exhibiting threshold current densities<300 A/cm² at 80 K. These values represent the state-of-the-art for mid-infrared lasers with λ>4 μm [reprint (PDF)]
19.	Effect of the spin split-off band on optical absorption in p-type Ga1 xInxAsyP1-y quantum-well infrared detectors J.R. Hoff, M. Razeghi and G. Brown Physical Review B 54 (15)-- October 15, 1996 ...[Visit Journal] Experimental investigations of p-type Ga_1-xIn_xAs_yP_1-y quantum-well intersubband photodetectors (QWIP’s) led to the discovery of unique features in photoresponse spectra of these devices. In particular, the strong 2–5 μm photoresponse of these QWIP’s was not anticipated based on previous experimental and theoretical results for p-type GaAs/Al_xGa_1-xAs QWIP’s. Our theoretical modeling of p-type QWIP’s based on the Ga_1-xIn_xAs_yP_1-y system revealed that the intense short-wavelength photoresponse was due to a much stronger coupling to the spin-orbit split-off components in the continuum than occurs for GaAs/Al_xGa_1-xAs QWIP’s. Due to the strong influence of the spin split-off band, an eight-band Kane Hamiltonian was required to accurately model the measured photoresponse spectra. This theoretical model is first applied to a standard p-type GaAs/Al_0.3Ga_0.7As QWIP, and then to a series of GaAs/Ga_0.51In_0.49P, GaAs/Ga_0.62In_0.38As_0.22P_0.78, Ga_0.79In_0.21As_0.59P_0.41/Ga_0.51In_0.49P, and Ga_0.79In_0.21As_0.59P_0.41/Ga_0.62In_0.38As_0.22P_0.78 QWIP’s. Through this analysis, the insignificance of spin split-off absorption in GaAs/Al_xGa_1-xAs QWIP’s is verified, as is the dual role of light-hole extended-state and spin split-off hole-extended-state absorption on the spectral shape of Ga_1-xIn_xAs_yP_1-y QWIP’s. [reprint (PDF)]
19.	Low frequency noise in 1024 x 1024 long wavelength infrared focal plane array base on Type-II InAs/GaSb superlattice A. Haddadi, S.R. Darvish, G. Chen, A.M. Hoang, B.M. Nguyen and M. Razeghi SPIE Proceedings, Vol. 8268, p. 82680X-- January 22, 2012 ...[Visit Journal] Recently, the type-II InAs/GaSb superlattice (T2SL) material platform is considered as a potential alternative for HgCdTe technology in long wavelength infrared (LWIR) imaging. This is due to the incredible growth in the understanding of its material properties and improvement of device processing which leads to design and fabrication of better devices. In this paper, we report electrical low frequency noise measurement on a high performance type-II InAs/GaSb superlattice 1024×1024 LWIR focal plane array. [reprint (PDF)]
19.	Reliability of Aluminum-Free 808 nm High-Power Laser Diodes with Uncoated Mirrors I. Eliashevich, J. Diaz, H. Yi, L. Wang, and M. Razeghi Applied Physics Letters 66 (23)-- June 5, 1995 ...[Visit Journal] The reliability of uncoated InGaAsP/GaAs high‐power diode lasers emitting at 808 nm wavelength has been studied. 47 W of quasicontinuous wave output power (pulse width 200 μs, frequency 20 Hz) have been obtained from a 1 cm wide laser bar. A single‐stripe diode without mirror coating has been life tested at 40 °C for emitting power of 800 mW continuous wave (cw) and showed no noticeable degradation and no change of the lasing wavelength after 6000 h of operation. [reprint (PDF)]
19.	High-power λ ~ 9.5 µm quantum-cascade lasers operating above room temperature in continuous-wave mode J.S. Yu, S. Slivken, A. Evans, S.R. Darvish, J. Nguyen, and M. Razeghi Applied Physics Letters, 88 (9)-- February 27, 2006 ...[Visit Journal] We report high-power continuous-wave (cw) operation of λ~9.5 μm quantum-cascade lasers to a temperature of 318 K. A high-reflectivity-coated 19-μm-wide and 3-mm-long device exhibits cw output powers as high as 150 mW at 288 K and still 22 mW at 318 K. In cw operation at 298 K, a threshold current density of 1.57 kA/cm², a slope efficiency of 391 mW/A, and a maximum wall-plug efficiency of 0.71% are obtained. [reprint (PDF)]
19.	Current status of high performance quantum cascade lasers at the center for quantum devices M. Razeghi; A. Evans; Y. Bai; J. Nguyen; S. Slivken; S.R. Darvish; K. Mi Conference Proceedings - International Conference on Indium Phosphide and Related Materials. 588-593:[4266015] (2007)-- May 14, 2007 ...[Visit Journal] Mid-infrared laser sources are highly desired for laser-based trace chemical sensors, military countermeasures, free-space communications, as well as developing medical applications. While application development has been limited by the availability of adequate mid-infrared sources, InP-based quantum cascade lasers (QCLs) hold promise as inexpensive, miniature, portable solutions capable of producing high powers and operating at high temperatures with excellent beam quality and superior reliability. This paper discusses the most recent developments of application-ready high power (> 100 mW), continuous-wave (CW), mid-infrared QCLs operating above room temperature with lifetimes exceeding 13,000 hours. [reprint (PDF)]

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