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51. | Dr. Stéphane Schilt, Université de Neuchâtel, SWITZERLAND Late-Breaking Results: Frequency Noise of a 4.6 µm DFB Quantum Cascade Laser measured from 130 K to 300 K Summary [+]  | Biography [+]  | Abstract [PDF]Speaker Biography: Dr Stéphane Schilt obtained his master degree in physics from the Swiss Federal Institute of Technology in Lausanne (EPFL) and his PhD in technical sciences in 2002 from the same institution for his work in trace gas sensing by laser spectroscopy. After a 3-year post-doc where he worked on photoacoustic spectroscopy and stabilized lasers, he joined the company IR Microsystems in Lausanne to develop low-cost gas sensors based on NIR lasers. Since 2009, he has been senior scientist at Laboratoire Temps-Fréquence at the University of Neuchâtel, Switzerland, where his research interest is focused on optical frequency combs for time and frequency metrology and QCL frequency-stabilization. He has published more than 25 papers in peer-reviewed journal and has co-authored over 50 contributions in international conferences. Summary: We present an experimental study of the evolution of the frequency noise in a 4.55-µm distributed feedback quantum cascade laser (QCL) measured over a wide temperature range of 128-303 K. The frequency noise power spectral density is measured using different carbon monoxide absorption lines used as a frequency-to-voltage converter. An abrupt transition is observed in the laser frequency noise near 200K: the frequency noise is almost unaltered at T > 200K, while it increases exponentially at lower temperature. The corresponding laser linewidth is larger by a factor ten at 128K (10 MHz) compared to the sub-MHz value achieved at room temperature. The origin of the frequency noise in the QCL is shown to result from internal electrical noise in the QCL structure. Indeed, measurements of the electrical noise of the laser (voltage noise across the laser) showed to follow the same trend with respect to temperature as the frequency noise and linewidth. ... Read Full Abstract [PDF] |
52. | Mr. Brian Simolon, FLIR Systems Inc., USA Late-Breaking Results: Two-color 640 x 512 CMOS ROIC for SLS detectors Summary [+]  | Biography [+]  | Abstract [PDF]Speaker Biography: Brian Simolon received the B.S. degree in computer engineering from the University of Notre Dame, Notre Dame, IN, in 2001 and the M.S. degree in electrical engineering from the University of California at Santa Barbara in 2004. He has been an integrated circuit (IC) design engineer at FLIR Systems since 2004. At FLIR he has designed mixed signal CMOS devices for infrared read out integrated circuits (ROICs) and read in integrated circuits (RIICs). He has worked on a wide variety of infrared ROICs including large and small format arrays, one and two-color arrays, and arrays for detectors operating at cryogenic temperatures. He has also designed arrays for microbolometers operating over large temperature ranges. Summary: The ISC0905 is a 640 x 512, large format, two-color CMOS readout integrated circuit (ROIC) designed for strained-layer superlattice (SLS) detectors. The detector interface is supported through one input pad in each 30 micron pixel. One bit in the serial control word programs the chip to automatically adjust all biases and timing to allow for the integration of either electrons or holes. This feature allows users to easily operate this ROIC with a wide variety of p-on-n or n-on-p detectors. The ROIC has been specifically designed to allow for both polarities of detectors to be placed back-to-back and to connect to the ROIC through a single input pad to obtain a two-color image. The two-color image is achieved by switching the ROIC mode between the two colors on a per frame basis. This presentation will describe the interface, design and features of the ISC0905 ROIC as well as results of ROIC testing and FPA imaging. ... Read Full Abstract [PDF] |
53. | Prof. Gunther Springholz, Johannes Kepler University Linz, AUSTRIA Late-Breaking Results: Quantum Dot Microcavity Lasers based on Epitaxial PbTe Dots Embedded in CdTe with 3.7 μm CW Mode Emission Summary [+]  | Biography [+]  | Abstract [PDF]Speaker Biography: Gunther Springholz studied physics at the Technical University in Graz and the University of Linz in Austria, where he received his PhD in 1993. Since 1998, he is an associate professor at the Institute for Semiconductor Physics of the University of Linz, where he is leading a research group on IV-VI and SiGe semiconductors. He is author or co-author of more than 260 scientific papers, including several review articles and book chapters. His current research interests are semiconductor hetero- and nanostructures with a focus on narrow gap semiconductors, mid-infrared optoelectronic devices as well as magnetic semiconductors and topological insulators. Summary: The first mid-infrared quantum dot lasers are demonstrated, fabricated from the PbTe/CdTe quantum dot system. The quantum dots are produced by a novel strain-free synthesis method, resulting in highly symmetric QDs without any 2D wetting layer on GaAs substrates. Due to the very large difference in band gaps, PbTe/CdTe QDs display strong MIR emission at room temperature and a wide wavelength tunability from λ c= 1.4 to 4 µm by control of the dot size. Free-standing microdisk structures show cw mid-infrared laser emission between 4.7 to 3.7 µm wavelength up to 200 K, and pulsed mode emission up to room temperature. ... Read Full Abstract [PDF] |
54. | Dr. Elizabeth Steenbergen, Air Force Research Labs, USA Late-Breaking Results: InAs/InAs1-xSbx superlattices on GaSb substrates: a promising alternative type-II superlattice infrared material system Summary [+]  | Biography [+]  | Abstract [PDF]Speaker Biography: Elizabeth Steenbergen is an engineer at the Air Force Research Lab. She received her MS and PhD in Electrical Engineering at Arizona State University in May 2009 and 2012, respectively. She accepted the Science Foundation Arizona fellowship and the DOD SMART scholarship during graduate school and was awarded the Palais Outstanding Doctoral Student award in Electrical Engineering at ASU. Summary: As one of the many promising antimonide Type-II superlattices (T2SLs), InAs/InAs 1-xSb x T2SLs have been proposed for MWIR and LWIR light emitting diodes, lasers, and photodetectors. Although MWIR and LWIR InAs/InAs 1-xSb x T2SL
structures grown on InAs substrates and GaSb substrates3 were successfully demonstrated in the 1990’s, they were set aside as a potential photodetector material in favor of the InAs/Ga1-xInxSb SL. Currently, the short minority carrier
lifetime, ~30 ns, of the InAs/Ga 1-xIn xSb T2SL limits the detector performance as evidenced by higher than predicted
dark currents and reduced quantum efficiencies. ... Read Full Abstract [PDF] |
55. | Mr. Rachid Taalat, Univ. Montpellier 2, FRANCE Late-Breaking Results: The influence of the InAs/GaSb SL period on the performance of type- II SL MWIR photodiodes Summary [+]  | Biography [+]  | Abstract [PDF]Speaker Biography: Rachid Taalat received his Master's degree in Physics and Engineering for microelectronics and nanotechnology materials from the University of Montpellier II, France, in 2010. he is currently pursuing the Ph.D. degree in Materials and Optronics systems at the Institut d'Electronique du Sud (IES) in Montpellier, France. My current research interests include device processing, optical and electrical characterizations of Type-II InAs/GaSb photodetectors. Summary: MWIR InAs/GaSb SL pin photodiodes were fabricated by MBE on p-type GaSb substrate. Symmetric SL structure was made of 8 InAs monolayers (MLs) and 8 GaSb MLs for λc = 4.5 µm at 80 K, while asymmetric SL design was composed of 7 InAs MLs and 4 GaSb MLs for λc = 5 µm at 80 K. Electro-optical characterizations including dark current, noise and C-V measurements, spectral response and quantum efficiency were performed on single detectors in the temperature range (77 K-300 K). Analysis of dark current characteristics shows that the R 0A value of asymmetric SL diode is improved by more than one decade in the whole range of temperature. ... Read Full Abstract [PDF] |
56. | Dr. Thierry Taliercio, Université Montpellier 2, FRANCE Late-Breaking Results: Surface and localized Plasmons Polaritons on arrays of doped and undoped semiconductors Summary [+]  | Biography [+]  | Abstract [PDF]Speaker Biography: Thierry Taliercio: was born in Aix en Provence (France) in 1970. Married and three children. He received the HDR (Habiliation à Diriger les Recherches) diploma in solid state physics in 2003 from the University of Montpellier. He is an associate professor in the Institut d’Electronique du Sud since 2008 (NANOMIR group). From 1999 to 2007, he was associate professor in the Groupe d'Etude des Semiconducteurs (GES in Montpellier-France). He is a specialist of the optical properties of nitride semiconductors and particularly of semiconductor nano-structures: small (GaInNAs) and wide (InGaN, GaN, AlN) band gap nitride semiconductors. He developed several experimental techniques to measure carriers decay times in semiconductor nano-structures in the infra-red as well as in the UV range within the frame of the ACI project BAND (2003-2006). He developed a micro-photoluminescence experiment in the UV range to study the optical properties of a single GaN/AlN quantum dot, supported by the ACI project BUGATI (2003-2006) and the ANR ZOOM. He developed several simulation tools to model the optical properties of semiconductor based nanostructures. He is now working on photo-voltage spectroscopy to characterize the density of states of mid-infra-red laser and an angular resolved reflectance and transmittance experiment in the IR range (1-20 μm) to study IR photonic and plasmonic nanostructures. Doctor Thierry Taliercio is author/co-author of 76 publications in refereed journals including 42 communications in international conferences and two book chapters. Its articles are quoted 1136 times and its impact factor is of 19. Summary: Surface plasmon polaritons (SPP) are excitations propagating at the interface between a dielectric and a conductor, arising from the coupling of the electromagnetic field and collective excitations of free electrons in the conductor. Many studies are based on metal nanostructures exploiting SPPs resonances from visible to mid-infrared frequencies. We focus our work on doped semiconductors. In contrast to metals, they offer the unique opportunity to adjust the plasma frequency by changing the doping. We recently proposed a theoretical model which describes the optical properties of an InAsSb/GaSb periodical nanostructure in a large range of frequency. The optical properties of these arrays are indeed strongly dependent on the geometry and on the dielectric constant of both materials. In this work, we validate experimentally the existence of SPP resonances in InAsSb and InAsSb/GaSb arrays and study the impact of several parameters. ... Read Full Abstract [PDF] |
57. | Dr. Ferechteh Hosseini Teherani, Nanovation, FRANCE Late-Breaking Results: Catalyst-free PLD Growth of Self-forming Moth-eye ZnO Nanostructure Arrays for IR Anti-Reflection Applications Summary [+]  | Biography [+]  | Abstract [PDF]Speaker Biography: Dr Ferechteh Hosseini Teherani: has been involved with the development of novel oxide materials and devices for over 25 years. After receiving her PhD from the University of Paris, Dr Teherani was a researcher at Thales (France), Nippon Telephone & Telegraph (Japan), Electrotechnical Laboratory (Japan) and Northwestern University (USA). In 2001, she went on to found a startup, Nanovation, of which she is currently CEO. Nanovation develops and commercialises ZnO thin films and nanostructures for optoelectronic applications. Dr. Teherani also has an MBA, has held an Eshbach Visiting Scholarship at Northwestern University and has been an expert for the European Commission since 2005. Dr. Teherani is author/co-author of over 115 papers and 8 patents. Summary: ZnO is wide bandgap material, which is being widely adopted as a transparent electrode thanks to
biocompatibility, low cost and transparencies/conductivities rivalling those of Indium Tin Oxide. ZnO also exhibits one of the largest families of nanostructures of all materials systems. Indeed, ZnO is one of the most researched nanomaterials and it is forecast to play an important role in a whole range of emerging optoelectronic applications. In previous studies it was demonstrated that Pulsed Laser Deposition (PLD) can give catalystfree, self-forming and vertically-aligned nanostructure arrays with superior crystallinity and optical
quality. The fact that these structures were self-forming and did not require a metal catalyst
simplifies the manufacturing and subsequent device fabrication. It was found that different nanostructure morphologies could be obtained by PLD including vertical, tapering and broadening nanostructures. Amongst these, the tapering “moth-eye type” arrays have shown excellent anti-reflection properties (<0.5% reflection) extending into the infrared for incidence angles up to over 60º which predispose them for use in detector/sensor, solar cell and LED applications.Although PLD gives nanostructures with excellent optical quality, the anisotropic plasma plume creates an inhomogeneous growth. This paper reports on the development of an approach to give uniform ZnO nanostructure array growth by PLD over 2 inch diameter wafers.
... Read Full Abstract [PDF] |
58. | Dr. Meimei Tidrow, U.S. Army NVESD, USA Late-Breaking Results: Overview of Strained Layer Superlattice Technology and Recent Progress in US Summary [+]  | Biography [+]  | Abstract [PDF]Speaker Biography: Dr. Meimei Tidrow holds the highest technical rank ST (Senior Technical Professional) in US government at the Army Night Vision Lab. She is the Chief Scientist at NVESD for FPAs. Prior to joining NVESD, Dr. Tidrow was an ST at the Missile Defense Agency (MDA) serving as the Technical Advisor to the Director of the Advanced Technology and the Program Manager for the Passive EO/IR Program. Prior to MDA, Dr. Tidrow was a Research Physicist at the Army Research Lab. She has extensive experience in III-V infrared material and device research. She has published more than 100 journal and conference papers and has given more than 70 invited talks in the infrared technology area. She is a Military Sensing Symposia (MSS) Fellow and SPIE Fellow. Summary: Antimony based type II strained layer superlattice (SLS) is a relatively new infrared detector material that holds great potential for future infrared systems in both military and commercial applications. This is the only infrared material that has a theoretical promise to exceed the HgCdTe performance at the same operating temperatures. In the past few years, rapid progress has been made in developing SLS-based infrared detectors and FPAs. The performance of these detectors and FPAs are approaching those made of HgCdTe materials. Fundamental studies on the minority carrier lifetimes also show great promise of this material to be able to compete with HgCdTe. This paper will give an overview of the SLS technologies and recent progress made in the US. Remaining technical issues and challenges will also be discussed. ... Read Full Abstract [PDF] |
59. | Prof. Frank Tittel, Rice Univ., USA Late-Breaking Results: Mid-Infrared semiconductor laser based trace gas sensor technologies: recent advances and applications Summary [+]  | Biography [+]  | Abstract [PDF]Speaker Biography: Frank Tittel (BA, MA, Ph.D. in physics) graduated from Oxford University in 1959. From 1959 to 1967 he was a Research Physicist with General Electric Research and Development Center, Schenectady, New York. Since 1967 he has been on the faculty of the Department of Electrical and Computer Engineering at Rice University in Houston, Texas. Current research interests include quantum electronics, especially laser spectroscopy, and applications in medicine, environmental monitoring, industrial process control and national security. Dr. Tittel is a Fellow of the IEEE, the Optical Society of America and the American Physical Society. He received a Doctor of Science (HC) degree from JATE University, Szeged, Hungary, in 1993. Summary: This talk will focus on recent advances in the development of sensors based on infrared semiconductor lasers for the detection, quantification and monitoring of trace gas species and their application in atmospheric chemistry, medical diagnostics, life sciences, industrial process control and national security. The development of compact trace gas sensors, in particular based on quantum cascade and interband cascade lasers permit the targeting of strong fundamental rotational-vibrational transitions in the mid-infrared. The architecture and performance of several sensitive, selective and real-time gas sensors based on mid-infrared semiconductor lasers will be described. High detection sensitivity at ppbv and sub-ppbv concentration levels requires a sensitivity enhancement scheme such as an optical multipass gas cell, cavity absorption enhancement technique, or photo-acoustic absorption spectroscopy. These three spectroscopic methods can achieve minimum detectable absorption losses in the range from 10 -8 to 10 -11 cm -1/√Hz. Recent examples of real world applications of field deployable gas sensors will be described. ... Read Full Abstract [PDF] |
60. | Dr. Virginie Trinite, Alcatel-Thales III-V Lab, FRANCE Late-Breaking Results: High Power Quantum Cascade Laser Arrays Summary [+]  | Biography [+]  | Abstract [PDF]Speaker Biography: Trinite Virginie: is born in France in 1979. She graduated from the Ecole Centrale de Paris, Paris, France in 2003 and received her PhD. Degree in physics from the Ecole Doctorale of Ecole Polytechnique, Palaiseau, France in 2006. She now works as researcher at Thales Research & Technology, Palaiseau, France since 2007. Her PhD focuses on the theoretical modeling of titanium phases by ab initio calculations. Her current research focuses on theoretical modeling of semiconductor hetero-structures for QWIP and Quantum Cascade Laser devices, and more specifically on electronic transport properties. Summary: One of the crucial points to have a high power quantum cascade laser (QCL) is to manage correctly the thermal effects. There are two ways of improving the efficiency of the laser: design a better active zone less sensitive to the elevation of the temperature as it as be done in or decrease the thermal resistance. We will introduce a new way to improve thermal dissipation by using μ-stripes array technology. These buried arrays are very appealing because they offer both lateral dissipation enhancement and beam quality control in large active region lasers. ... Read Full Abstract [PDF] |
61. | Prof. Joachim Wagner, Fraunhofer-Institut für Angewandte Festkörperphysik (IAF), GERMANY Late-Breaking Results: Recent advances in power scaling and narrow linewidth operation of 2 μm GaSb-based semiconductor disk lasers Summary [+]  | Biography [+]  | Abstract [PDF]Speaker Biography: Joachim Wagner received the Ph.D. degree in physics from the University of Stuttgart, Stuttgart, Germany, in 1982. From 1982 to 1984 he worked at the “Max-Planck-Institut für Festkörperforschung”, Stuttgart, Germany, in the group of Prof. M. Cardona before joining the Fraunhofer-Institut for Applied Solid State Physics, Freiburg, Germany, in 1985. There he is currently deputy director and head of the Department of “Optoelectronic Modules”. He is also Professor at the Institute of Physics of the University of Freiburg and an associated member of the Materials Research Center Freiburg (FMF). His current research interests include III/Vsemiconductor heterostructures and their application in optoelectronic devices both for the infrared and the visible/uv spectral range. He is author or coauthor of more than 400 scientific publications including several review papers and book chapters. Summary: The (AlGaIn)(AsSb) semiconductor materials system has been shown to be ideally suited to realize optically pumped Semiconductor Disk Lasers (SDL), also known as Vertical External Cavity Surface Emitting Lasers (VECSELs), for the 2-3 µm wavelength range. ... Read Full Abstract [PDF] |
62. | Dr. Eliezer Weiss, SCD Semiconductor Devices, ISRAEL Late-Breaking Results: InAsSb-Based Bariodes Grown on GaAs Covering the Whole MWIR Atmospheric Window Summary [+]  | Biography [+]  | Abstract [PDF]Speaker Biography: Eliezer (Eli) Weiss received his B.Sc. (1975) and D.Sc. (1984) in physical chemistry from the Technion, Israel Institute of Technology. From 1984 he is with SCD. In 1989 - 1990 Eli was a research-associate in Stanford University. From 1991 to 2001 he was the manager of SCD's Crystal Growth deportment, responsible for the development and production of HgCdTe crystal and epi-layers as well as the growth of III-V epi-wafers. Since 2001 he has been the Vice President for Technologies R&D in SCD. Eli has published 1 patent and more than 40 refereed and conference papers. Summary: XBnn mid-wave infrared (MWIR) detector arrays are aimed at high operating temperature (HOT) applications and are based on device elements with an InAsSb/AlSbAs heterostructure. Also known as barrier detectors or "bariodes", there is no depletion layer in the narrow-bandgap active layer of such devices. The usual Generation-Recombination (G-R) and Trap Assisted Tunneling (TAT) mechanisms for dark current in standard narrow bandgap diodes are totally suppressed in bariodes, leading to much lower dark currents in bariode detectors with the same bandgap wavelength. InAsSb bariode detectors, grown by molecular beam epitaxy (MBE) on lattice matched GaSb substrates and operating at 150 K have been shown previously to exhibit low dark current densities of ~10 -7 A/cm 2. The ability to operate a bariode IR detector at a higher temperature than a standard photodiode results in an improved range of solutions for various applications, especially where the size, weight, and power (SWaP) are critical. By raising the FPA operating temperature from 80 K to 150 K the required cooling power is reduced by about 60%, yielding advantages such as: faster cool-down time and mission readiness, lower cooling power, higher cooler reliability, and more compact detectors for volume-critical applications. ... Read Full Abstract [PDF] |
63. | Mr. Michael Witzan, Johannes Kepler University Linz, AUSTRIA Late-Breaking Results: Comparison of MIR PbTe and PbSe quantum well microdisk lasers Summary [+]  | Biography [+]  | Abstract [PDF]Speaker Biography: Michael Witzan started his study in technical physics at the Johannes Kepler University of Linz, Austria, in 2003. In 2010 he began to work on his master thesis in the IV-VI semiconductor research group of Prof. Gunther Springholz. Currently, he is finishing the master thesis and will start right afterwards with his Ph.D in the group of Prof. Springholz at JKU. His current research interests include the design, fabrication and characterization of IV-VI semiconductor structures and devices. Summary: Coherent mid-infrared (MIR) optical emitters are extremely useful for high-sensitive gas analysis. For such devices, the lead salt compounds are very well suited because of their favorable optically direct band structure and low nonradiative Auger recombination rates. In particular, their wide wavelength tunability makes IV-VI lasers attractive for spectroscopy application. Up to now, however, continuous-wave operation was limited to 135 K for VCSELs and 223 K for edge emitters. In this work, we realized optically pumped microdisk lasers with PbTe/PbSrTe quantum well as active regions. Similar to our previews work we varied the single PbTe quantum well thickness, and compared the result with microdisk lasers based on PbSe quantum wells. The maxium cw-mode laser operation temperature of PbTe/PbSrTe microdisk lasers are around 100 K lower than the PbSe/PbSrSe microdisk. ... Read Full Abstract [PDF] |
64. | Prof. Yury Yakovlev, Ioffe Physico-Technical Institute, RUSSIA Late-Breaking Results: Highly tunable whispering gallery mode semiconductor lasers with controlled absorber Summary [+]  | Biography [+]  | Abstract [PDF]Speaker Biography: Yury P.Yakovlev was born on October 17, 1939. He graduated with a M.Sc. degree from the Leningrad Electrical Engineering Institute in 1962 and jointed Ioffe Physico-Technical Institute in 1969. He received his Ph.D. degree in 1978 and the Doctor of Science degree in 1995 both in physics and mathematics from Ioffe Institute. His main research interests are technology and researches of narrow band gap III-V solid alloys heterostructures and optoelectronic devices (LED, Lasers and Photodiodes). In 1995, Yury Yakovlev organized and headed the Laboratory of Infrared Optoelectronics (LIRO) in Ioffe Institute. Prof. Yury P. Yakovlev has authored or co-authored 80 patents, over 200 papers, reviews and book chapters. Summary: Tunable semiconductor lasers with controlled absorber based on GaInAsSb/GaAlAsSb quantum well heterostructure was fabricated and experimentally studied. The emission wavelength of these lasers shifts from 2.24 to 2.28 μm when the bias on the control contact decreases from the voltage equal to that on the main electrode to 0 V when the control contact is grounded. The principle of operation of such a device is given ... Read Full Abstract [PDF] |
65. | Dr. Rui Yang, Univ of Oklahoma, USA Late-Breaking Results: Recent Progress in InAs-based Interband Cascade Lasers Summary [+]  | Biography [+]  | Abstract [PDF]Speaker Biography: Dr. Yang received his Ph.D in physics in 1987. He is a professor at the University of Oklahoma (OU) with research activities in semiconductor quantum devices such as mid-infrared lasers and detectors, and photovoltaic devices. Prior to joining OU 2007, he was a Principal Member of Engineering Staff and a Task Manager at the Jet Propulsion Laboratory (JPL), where he led the development of interband cascade lasers for applications in Earth sciences and planetary explorations. He received the Edward Stone Award in 2007 from JPL for outstanding research publication and the successful accelerated infusion of cutting-edge interband cascade semiconductor laser technology into flight mission readiness. Summary: After about 16 years of exploration and development, interband cascade (IC) lasers have now been proven to be capable of continuous wave (cw) operation at room temperature and above for a wide wavelength range of 2.9 to 5.7 μm in the mid-infrared spectral region. In contrast to quantum cascade (QC) lasers based on intersubband transitions, IC lasers circumvent the fast phonon scattering issue by using the transition between conduction and valence bands for photon emission. As such, the threshold current density is significantly lowered with high voltage efficiency, resulting low power consumption. Here, we will present our recent progress in InAs based IC lasers, which use plasmon cladding layer to replace superlattice cladding, resulting in improved thermal dissipation and extended lasing wavelengths of IC lasers. ... Read Full Abstract [PDF] |
66. | Dr. Yong-gang Zhang, Shanghai Institute of Microsystem and Information Technology, CHINA Late-Breaking Results: Emission spectroscopy in MIR using FTIR: an overview Summary [+]  | Biography [+]  | Abstract [PDF]Speaker Biography: Zhang Yong-gang: received B.S degree in semiconductor device from Nanjing Institute of Posts and Telecommunications, China in 1982, M.S and Ph.D. degrees in semiconductor physics from Shanghai Institute of Metallurgy, Chinese Academy of Sciences in 1987 and 1996 respectively. He had been a worker during 1975-1978, and a teacher during 1982-1984. He joined Shanghai Institute of Metallurgy (now named Shanghai Institute of Microsystem and Information Technology), Chinese Academy of Sciences since 1987, his research interests include III-V semiconductor optoelectronic materials, devices and applications. He had been a research professor at the State Key Laboratory of Functional Materials for Informatics since 1996, and supervised more than 20 Ph.D. and M. S. students there. He was a senior member of IEEE. Summary: For most FTIR instruments an emission port has been included, through this port the spectral features from external emission sources of materials and devices, such as lasing, photoluminescence (PL) and electroluminescence (EL), could be characterized. Based on this arrangement, accessional user configurations for different approaches have been developed. Acquiring relatively strong PL signals apart from the background using conventional rapid scan mode of FTIR are valid. This mode is also effective for device characterization, such as the narrow band emission spectrum of quantum well lasers and quantum cascade lasers (QCLs) with enough lasing power in MIR, regardless of continuous wave or pulsed operation. However, because in certain cases the signal is often quite weak, and in many cases they are even much weaker than the room temperature thermal background radiation or stray light background, so extracting weak signal from the background and keeping the convenience of FTIR remains a challenge. In this work, with the comparative analysis of the system, an improved FTIR accessional configuration has been developed. In this approach three different modes of rapid scan, double modulation or step scan were software switchable without changing of the hardware or connections. The advantages and drawbacks of each mode were discussed in detail. Using this approach a group of emission samples in MIR with quite different intensities have been characterized to demonstrate the system validity. ... Read Full Abstract [PDF] |
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