Search Results - "Gmachl, C.F."

Room-temperature continuous-wave quantum cascade lasers grown by MOCVD without lateral regrowth by Zhijun Liu, Wasserman, D., Howard, S.S., Hoffman, A.J., Gmachl, C.F., Xiaojun Wang, Tanbun-Ek, T., Liwei Cheng, Fow-Sen Choa

“…We report on room-temperature continuous-wave (CW) operation of /spl lambda//spl sim/8.2 μm quantum cascade lasers grown by metal-organic chemical vapor…”
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Thermal and Stark-Effect Roll-Over of Quantum-Cascade Lasers by Howard, S.S., Zhijun Liu, Gmachl, C.F.

“…A computational and experimental analysis of rollover in high-performance lambda ~ 8 mum quantum-cascade (QC) lasers is presented. In addition to conventional,…”
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High-Performance Quantum Cascade Lasers: Optimized Design Through Waveguide and Thermal Modeling by Howard, S.S., Zhijun Liu, Wasserman, D., Hoffman, A.J., Ko, T.S., Gmachl, C.F.

“…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…”
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A Compact Four-Wavelength Quantum-Cascade Laser Source by Toor, F., Howard, S.S., Sivco, D.L., Gmachl, C.F.

“…A four-wavelength quantum-cascade (QC) laser source that operates using a single current channel is presented. The source includes two different heterogeneous…”
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Rapid and Minimally Invasive Quantum Cascade Wafer Testing by Bentil, E.N., Toor, F., Hoffman, A.J., Escarra, M.D., Gmachl, C.F.

“…In this work, we demonstrate a rapid and minimally invasive technique for wafer quality testing, which requires using a single etch and metallization step to…”
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Characterization of Quantum-Cascade Lasers Using Single-Pass Transmission Spectroscopy by Dirisu, A.O., Revin, D.G., Zhijun Liu, Kennedy, K., Cockburn, J.W., Gmachl, C.F.

“…The study of the electron distribution and intersubband transitions in quantum cascade (QC) lasers provides fundamental insights into the laser operation…”
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Voltage Tunability of Quantum Cascade Lasers by Yao, Yu, Liu, Zhijun, Hoffman, Anthony J., Franz, Kale J., Gmachl, Claire F.

“…The voltage tunability of three types of quantum cascade laser designs is investigated. The tuning coefficients and tuning ranges of electroluminescence and…”
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Reduction of Facet Reflectivity of Quantum-Cascade Lasers With Subwavelength Gratings by Dirisu, A.O., Silva, G., Zhijun Liu, Gmachl, C.F., Towner, F.J., Bruno, J., Sivco, D.L.

“…We demonstrate the reduction of the facet reflectivity of quantum-cascade lasers (QCLs) by using subwavelength gratings. The gratings were fabricated on…”
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Temperature Dependence of Optical Gain and Loss in [Formula Omitted] 8.2-10.2 [Formula Omitted]m Quantum-Cascade Lasers by Liu, Zhijun, Gmachl, C F, Cheng, Liwei, Choa, Fow-Sen, Towner, F J, Wang, Xiaojun, Fan, Jenyu

“…Temperature-dependent optical gain and waveguide loss have been measured for continuous-wave operated quantum-cascade lasers with wavelengths between 8.2 and…”
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Temporal wavelength multiplexing of a Quantum Cascade laser by Toor, F., Sivco, D.L., Gmachl, C.F.

“…A bi-directional and multi-wavelength Quantum Cascade (QC) laser based system is presented that is both time and wavelength multiplexed, that is, it can emit…”
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Solution-cast As2S3 raised strip waveguides for integrated mid-ir optics by Tsay, C., Mujagic, E., Gmachl, C.F., Arnold, C.B.

“…The development of planar chalcogenide glass waveguides leads the way toward integrated mid-infrared optics. As 2 S 3 waveguides fabricated by solution casting…”
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Analysis of the Thermal Roll-Over of Quantum Cascade Lasers by Howard, S.S., Zhijun Liu, Gmachl, C.F.

“…A description of thermal roll-over in room temperature continuous-wave operating quantum cascade lasers is presented. Models predicting maximum operating…”
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Solvent-casting of Photo-refractive Chalcogenide Glasses and their Application in Quantum Cascade Laser Tuning by Shanshan Song, Gmachl, C.F., Arnold, C.B.

“…We deposited photo-modifiable chalcogenide films through a low-temperature, solvent-casting technique. Their thermal and optical properties were characterized…”
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Widely voltage tunable quantum cascade lasers by Yu Yao, Franz, K.J., Xiaojun Wang, Jen-Yu Fan, Gmachl, C.F.

“…A new Quantum Cascade laser design with a ldquotwo-steprdquo coupling between the injector and the active region provides a voltage tuning range of 200 cm -1…”
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Role of interface roughness in the transport and lasing characteristics of quantum-cascade lasers by Khurgin, J.B., Dikmelik, Y., Liu, P.Q., Hoffman, A.J., Escarra, M.D., Franz, K.J., Gmachl, C.F.

“…A density-matrix based theory of transport and lasing in quantum-cascade lasers reveals that large disparity between lasing linewidth and tunneling broadening…”
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Intersubband absorption loss in high-performance mid-infrared quantum cascade lasers by Dikmelik, Y., Khurgin, J.B., Escarra, M.D., Liu, P.Q., Hoffman, A.J., Franz, K.J., Gmachl, C.F., Fan, J., Xiaojun Wang

“…We calculate intersubband absorption loss and report measured waveguide loss for two high-performance mid-infrared quantum cascade laser designs. Intersubband…”
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Quantum Cascade Lasers with ultra-strong coupling injection by Liu, P.Q., Hoffman, A.J., Escarra, M.D., Franz, K.J., Khurgin, J.B., Dikmelik, Y., Xiaojun Wang, Jen-Yu Fan, Gmachl, C.F.

“…We demonstrate a Quantum Cascade Laser employing ultra-strong (~20 meV) coupling between the injector and the upper laser state. The laser shows a pulsed…”
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Enhancing wavelength selection for Quantum Cascade laser based chemical sensors by cavity length variation by Young, C., Cendejas, R., Howard, S.S., Sanchez-Vaynshteyn, W., Hoffman, A.J., Franz, K.J., Yu Yao, Mizaikoff, B., Xiaojun Wang, Fan, J., Gmachl, C.F.

“…Varying quantum cascade laser cavity length results in gain peak selection across a 118 cm -1 range; a result of a change in threshold voltage, and applied…”
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Design and deployment of a quantum cascade laser absorption spectrometer in an open-path sensor system for trace gas analysis by Michel, A.P.M., Liu, P.Q., Yeung, J.K., Corrigan, P., Baeck, M.L., Xiaole Pan, Huabin Dong, Zifa Wang, Day, T., Smith, J.A., Moshary, F., Gmachl, C.F.

“…A widely tunable, external cavity quantum cascade laser was used in the deployment of an open-path sensor for the measurement of water vapor, ozone, ammonia,…”
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Growth Studies of Quantum Cascade Lasers With Current-Blocking Structures by Liwei Cheng, Xiaoming Ji, Fow-Sen Choa, Zhijun Liu, Gmachl, C.F., Fan, J., Xiaojun Wang, Leavitt, R., Bruno, J., Bradshaw, J.

“…Buried-heterosturcture regrowths have very significant impact on quantum-cascade- laser (QCL) threshold, output power, and reliability. We report detailed BH…”
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