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1.  Aluminum free GaInP/GaAs Quantum Well Infrared Photodetectors for Long Wavelength Detection
C. Jelen, S. Slivken, J. Hoff, M. Razeghi, and G. Brown
Applied Physics Letters 70 (3)-- January 20, 1997 ...[Visit Journal]
We demonstrate quantum well infrared photodetectors based on a GaAs/Ga0.51In0.49P superlattice structure grown by gas-source molecular beam epitaxy. Wafers were grown with varying well widths. Wells of 40, 65, and 75 Å resulted in peak detection wavelengths of 10.4, 12.8, and 13.3 μm with a cutoff wavelength of 13.5, 15, and 15.5 μm, respectively. The measured peak and cutoff wavelengths match those predicted by eight band theoretical analysis. Measured dark currents were lower than equivalent GaAs/AlGaAs samples. [reprint (PDF)]
 
1.  AlGaN ultraviolet photoconductors grown on sapphire
D. Walker, X. Zhang, P. Kung, A. Saxler, S. Javadpour, J. Xu, and M. Razeghi
Applied Physics Letters 68 (15)-- April 8, 1996 ...[Visit Journal]
AlxGa1−xN (0≤x≤0.50) ultraviolet photoconductors with a minimum cutoff wavelength shorter than 260 nm have been fabricated and characterized. The AlGaN active layers were grown on (00⋅1) sapphire substrates by metalorganic chemical vapor deposition (MOCVD). The spectral responsivity of the GaN detector at 360 nm is about 1 A/W biased at 8 V at room temperature. The carrier lifetime derived from the voltage‐dependent responsivity is 0.13–0.36 ms. [reprint (PDF)]
 
1.  Thermal stability of GaN thin films grown on (0001) Al2O3, (0112) Al2O3 and (0001)Si 6H-SiC substrates
C.J. Sun, P. Kung, A. Saxler, H. Ohsato, E. Bigan, M. Razeghi, and D.K. Gaskill
Journal of Applied Physics 76 (1)-- July 1, 1994 ...[Visit Journal]
Single crystals of GaN were grown on (0001), (0112) Al2O3 and (0001)Si 6H‐SiC substrates using an atmospheric pressure metalorganic chemical‐vapor‐deposition reactor. The relationship has been studied between the thermal stability of the GaN films and the substrate’s surface polarity. It appeared that the N‐terminated (0001) GaN surface grown on (0001)Si 6H‐SiC has the most stable surface, followed by the nonpolar (1120) GaN surface grown on (0112) Al2O3, while the Ga‐terminated (0001) GaN surface grown on (0001) Al2O3 has the least stable surface. This is explained with the difference in the atomic configuration of each of these surfaces which induces a difference in their thermal decomposition. [reprint (PDF)]
 
1.  Molecular beam epitaxial growth of InSb p-i-n photodetectors on GaAs and Si
E. Michel, R. Peters, S. Slivken, C. Jelen, P. Bove, J. Xu, I. Ferguson, and M. Razeghi
Optoelectronic Integrated Circuit Materials, Physics and Devices, SPIE Conference, San Jose, CA; Proceedings, Vol. 2397-- February 6, 1995 ...[Visit Journal]
High quality InSb has been grown by Molecular Beam Epitaxy and optimized using Reflection High Energy Electron Diffraction. A 4.8 micrometers InSb layer grown on GaAs at a growth temperature of 395 degree(s)C and a III/V incorporation ratio of 1:1.2 had an X-ray rocking curve FWHM of 158 arcsec and a Hall mobility of 92300 cm2V-1s-1 at 77 K, the best reported to date for InSb nucleated directly onto GaAs. InSb p-i-n structures of 5.8 micrometers grown under the same conditions demonstrated a X-ray Full Width at Half Maximum of 101 arcsec and 131 arcsec for GaAs and Si substrates, respectively, and exhibited excellent uniformity of +/- 3 arcsec over a 3' substrate. Prototype InSb p-i-n detectors on Si have been fabricated and have demonstrated photovoltaic response at 6.5 micrometers up to 200 K. These p-i-n detectors have also exhibited the highest D* for a device grown onto Si. [reprint (PDF)]
 
1.  Efficiency of photoluminescence and excess carrier confinement in InGaAsP/GaAs structures prepared by metal-organic chemical vapor deposition
J. Diaz, H.J. Yi, M. Erdtmann, X. He, E. Kolev, D. Garbuzov, E. Bigan, and M. Razeghi
Journal of Applied Physics 76 (2)-- July 15, 1994 ...[Visit Journal]
Special double‐ and separate‐confinement InGaAsP/GaAs heterostructures intended for photoluminescence measurements have been grown by low‐pressure metal‐organic chemical‐vapor deposition. The band gap of the active region quaternary material was close to 1.5 eV, and the waveguide of the separate‐confinement structures was near 1.8 eV. Measurement of the integrated luminescence efficiency at 300 K has shown that over a wide range of excitation level (10–103 W/cm²) radiative transitions are the dominant mechanism for excess carrier recombination in the active region of the structures studied. As determined by spectral measurements, the excess carrier concentration in the waveguide of the separate‐confinement heterostructures and the intensity of the waveguide emission band correspond to a condition of thermal equilibrium of the excess carrier populations in the active region and the waveguide. The ratio of the intensity of the waveguide emission to the active region emission fits a model which assumes that the barrier height for minority carriers (holes) is equal to the difference in band gaps between the active region and the waveguide region. [reprint (PDF)]
 
1.  Room temperature compact THz sources based on quantum cascade laser technology
M. Razeghi; Q.Y. Lu; N. Bandyopadhyay; S. Slivken; Y. Bai
Proc. SPIE 8846, Terahertz Emitters, Receivers, and Applications IV, 884602 (September 24, 2013)-- November 24, 2013 ...[Visit Journal]
We present the high performance THz sources based on intracavity difference-frequency generation from mid-infrared quantum cascade lasers. Room temperature single-mode operation in a wide THz spectral range of 1-4.6 THz is demonstrated from our Čerenkov phase-matched THz sources with dual-period DFB gratings. High THz power up to 215 μW at 3.5 THz is demonstrated via epi-down mounting of our THz device. The rapid development renders this type of THz sources promising local oscillators for many astronomical and medical applications. [reprint (PDF)]
 
1.  High power, continuous wave, quantum cascade ring laser
Y. Bai, S. Tsao, N. Bandyopadhyay, S. Slivken, Q.Y. Lu, D. Caffey, M. Pushkarsky, T. Day and M. Razeghi
Applied Physics Letters, Vol. 99, No. 26, p. 261104-1-- December 26, 2011 ...[Visit Journal]
We demonstrate a quantum cascade ring laser with high power room temperature continuous wave operation. A second order distributed feedback grating buried inside the waveguide provides both in-plane feedback and vertical power outcoupling. Total output power reaches 0.51 W at an emission wavelength around 4.85 μm. Single mode operation persists up to 0.4 W. The far field analysis indicates that the device operates in a high order mode. The magnetic and electric components of the ring-shaped lasing beam are in radial and azimuthal directions, respectively. [reprint (PDF)]
 
1.  Reliability in room-temperature negative differential resistance characteristics of low-aluminum contact AlGaN/GaN double-barrier resonant tunneling diodes
C. Bayram, Z. Vashaei, and M. Razeghi
Applied Physics Letters, Vol. 97, No. 18, p. 181109-1-- November 1, 2010 ...[Visit Journal]
AlGaN/GaN resonant tunneling diodes (RTDs), consisting of 20% (10%) aluminum-content in double-barrier (DB) active layer, were grown by metal-organic chemical vapor deposition on freestanding polar (c-plane) and nonpolar (m-plane) GaN substrates. RTDs were fabricated into 35-μm-diameter devices for electrical characterization. Lower aluminum content in the DB active layer and minimization of dislocations and polarization fields increased the reliability and reproducibility of room-temperature negative differential resistance (NDR). Polar RTDs showed decaying NDR behavior, whereas nonpolar ones did not significantly. Averaging over 50 measurements, nonpolar RTDs demonstrated a NDR of 67 Ω, a current-peak-to-valley ratio of 1.08, and an average oscillator output power of 0.52 mW. [reprint (PDF)]
 
1.  GaN avalanche photodiodes grown on m-plane freestanding GaN substrate
Z. Vashaei, E. Cicek, C. Bayram, R. McClintock and M. Razeghi
Applied Physics Letters, Vol. 96, No. 20, p. 201908-1-- May 17, 2010 ...[Visit Journal]
M-plane GaN avalanche p-i-n photodiodes on low dislocation density freestanding m-plane GaN substrates were realized using metal-organic chemical vapor deposition. High quality homoepitaxial m-plane GaN layers were developed; the root-mean-square surface roughness was less than 1 Å and the full-width-at-half-maximum value of the x-ray rocking curve for (1010) diffraction of m-plane GaN epilayer was 32 arcsec. High quality material led to a low reverse-bias dark current of 8.11 pA for 225 μm² mesa photodetectors prior to avalanche breakdown, with the maximum multiplication gain reaching about 8000. [reprint (PDF)]
 
1.  Fabrication and characterization of novel hybrid green light emitting didoes based on substituting n-type ZnO for n-type GaN in an inverted p-n junction
C. Bayram, D. Rogers, F. H. Teherani, and M. Razeghi
Journal of Vacuum Science and Technology B, Vol. 27, No. 3, May/June, p. 1784-1788-- May 29, 2009 ...[Visit Journal]
Details of the fabrication and characterization of hybrid green light emitting diodes, composed of n-ZnO/(InGaN/GaN) multi-quantum-wells/p-GaN on AlN/sapphire, are reported. Scanning electron microscope, atomic force microscopy, high resolution x-ray diffraction, and photoluminescence were used to study the hybrid device. The effects of solvents, annealing, and etching on n-ZnO are discussed. Successful hybridization of ZnO and (In)GaN into a green light emitting diode was realized. [reprint (PDF)]
 
1.  Back-illuminated separate absorption and multiplication GaN avalanche photodiodes
J.L. Pau, C. Bayram, R. McClintock, M. Razeghi and D. Silversmith
Applied Physics Letters, Vol. 92, No. 10, p. 101120-1-- March 10, 2008 ...[Visit Journal]
The performance of back-illuminated avalanche photodiodes with separate absorption and multiplication regions is presented. Devices with an active area of 225 µm2 show a maximum multiplication gain of 41,200. The calculation of the noise equivalent power yields a minimum value of 3.3×10−14 W·Hz−1/2 at a gain of 3000, increasing to 2.0×10−13 W·Hz−1/2 at a gain of 41,200. The broadening of the response edge has been analyzed as a function of bias. [reprint (PDF)]
 
1.  ZnO 3D flower-like nanostructure synthesized on GaN epitaxial layer by simple route hydrothermal process
J.M. Jung, C.R. Kim, H. Ryu, M. Razeghi and W.G. Jung
Journal of Alloys and Compounds-- September 15, 2007 ...[Visit Journal]
The 3D type, flower-like ZnO nanostructures from particle to flower-like or chestnut bur are fabricated on the GaN epitaxial layer substrate through the simple-route hydrothermal process. Structural characterization was made for the ZnO 3D nanostructures synthesized in different pH ranging from 9.5 to 11.0. The growth model was proposed and discussed regarding the fabrication mechanism and morphology of ZnO 3D flower-like nanostructure. The flower-like ZnO is composed of many thin single crystals ZnO nanorods. Bigger and thicker ZnO structure is fabricated with the increase of pH in solution. The enhanced UV emission in the PL measurement and the spectra in the Raman spectroscopy for ZnO–GaN heterojunction material were discussed. [reprint (PDF)]
 
1.  Near bulk-limited R0A of long-wavelength infrared type-II InAs/GaSb superlattice photodiodes with polyimide surface passivation
Andrew Hood, Pierre-Yves Delaunay, Darin Hoffman, Binh-Minh Nguyen, Yajun Wei, Manijeh Razeghi, and Vaidya Nathan
Applied Physics Letters 90, 233513-- June 4, 2007 ...[Visit Journal]
Effective surface passivation of Type-II InAs/GaSb superlattice photodiodes with cutoff wavelengths in the long-wavelength infrared is presented. A stable passivation layer, the electrical properties of which do not change as a function of the ambient environment nor time, has been prepared by a solvent-based surface preparation, vacuum desorption, and the application of an insulating polyimide layer. Passivated photodiodes, with dimensions ranging from 400×400 to 25×25 µm2, with a cutoff wavelength of ~11 µm, exhibited near bulk-limited R0A values of ~12 Ω·cm2, surface resistivities in excess of 104 Ω·cm, and very uniform current-voltage behavior at 77 K. [reprint (PDF)]
 
1.  Improved performance of quantum cascade lasers via manufacturable quality epitaxial side down mounting process utilizing aluminum nitride heatsinks
A. Tsekoun, R. Go, M. Pushkarsky, M. Razeghi, C.K.N. Patel
SPIE Conference, San Jose, CA, Vol. 6127, pp. 612702-- January 23, 2006 ...[Visit Journal]
We report substantially improved performance of high power quantum cascade lasers by utilizing epi-side down mounting that provides superior heat dissipation properties. We have obtained CW power output of 450 mW at 20°C from mid-IR QCLs. The improved thermal management achieved with epi-side down mounting has also permitted us to carry out initial lifetime tests on the mid-IR QCLs. No degradation of power output is seen even after over 300 hours of CW operation at 25°C with power output in excess of 300 mW. We believe these improvements should permit incorporation of mid-IR QCLs in reliable instrumentation. [reprint (PDF)]
 
1.  High Quantum Efficiency Solar-Blind Photodetectors
R. McClintock, A. Yasan, K. Mayes, D. Shiell, S. Darvish, P. Kung and M. Razeghi
SPIE Conference, Jose, CA, Vol. 5359, pp. 434-- January 25, 2004 ...[Visit Journal]
We report AlGaN-based back-illuminated solar-blind p-i-n photodetectors with a record peak responsivity of 150 mA/W at 280 nm, corresponding to a high external quantum efficiency of 68%, increasing to 74% under 5 volts reverse bias. Through optimization of the p-AlGaN layer, we were able to remove the out-of-band negative photoresponse originating from the Schottky-like p-type metal contact, and hence significantly improve the degree of solar-blindness [reprint (PDF)]
 
1.  Very High Average Power Quantum Cascade Lasers by GasMBE
S. Slivken and M. Razeghi
SPIE Conference, San Jose, CA, Vol. 4999, pp. 59-- January 27, 2003 ...[Visit Journal]
Very high average power QCLs are demonstrated within the 5.8 - 9 µm wavelength range. At longer wavelengths, scaling of the power is demonstrated by increasing the number of emitting regions in the waveguide core. At λ = 9 µm, over 3.5 W of peak power per facet has been demonstrated at room temperature for a single 25 µm by 3 mm diode, with an average power of 150 mW at 6% duty cycle. At shorter wavelengths, highly strain-balanced heterostructures are used to create a high coduction band offset and minimize leakage current. At λ = 6 µm, utilizing a high reflective coating and epilayer-down mounting of the laser, we demonstrate 225 mW of average power from a single facet at room temperature. Increasing the conduction band offset further and optimizing the doping in the injector region has led to demonstration of > 250 mW average power (λ = 5.8 µm) at > 50% duty cycle for a 20 µm by 2 mm HR coated diode bonded epilayer-down to a copper heatsink. Also at room temperature, use of Au electroplating and wider ridges has allowed us to further demonstrate without epilayer-down bonding, 0.67 W average power at 17% duty cycle from a single 40 µm by 2 mm HR coated laser. [reprint (PDF)]
 
1.  Type-II InAs/GaSb Superlattices and Detectors with Cutoff Wavelength Greater Than 18 μm
M. Razeghi, Y. Wei, A. Gin, G.J. Brown and D. Johnstone
Proceedings of the SPIE, San Jose, CA, Vol. 4650, 111 (2002)-- January 25, 2002 ...[Visit Journal]
The authors report the most recent advances in Type-II InAs/GaSb superlattice materials and photovoltaic detectors. Lattice mismatch between the substrate and the superlattice has been routinely achieved below 0.1%, and less than 0.0043% as the record. The FWHM of the zeroth order peak from x-ray diffraction has been decreased below 50 arcsec and a record of less than 44arcsec has been achieved. High performance detectors with 50% cutoff beyond 18 micrometers up to 26 micrometers have been successfully demonstrated. The detectors with a 50% cut-off wavelength of 18.8 micrometers showed a peak current responsivity of 4 A/W at 80K, and a peak detectivity of 4.510 cm·Hz½·W-1 was achieved at 80K at a reverse bias of 110 mV under 300 K 2(pi) FOV background. Some detectors showed a projected 0% cutoff wavelength up to 28~30 micrometers . The peak responsivity of 3Amp/Watt and detectivity of 4.2510 cm·Hz½·W-1 was achieved under -40mV reverse bias at 34K for these detectors. [reprint (PDF)]
 
1.  Growth and Characterization of Type-II Non-Equilibrium Photovoltaic Detectors for Long Wavelength Infrared Range
H. Mohseni, J. Wojkowski, A. Tahraoui, M. Razeghi, G. Brown and W. Mitche
SPIE Conference, San Jose, CA, -- January 26, 2000 ...[Visit Journal]
Growth and characterization of type-II detectors for mid-IR wavelength range is presented. The device has a p-i-n structure is designed to operate in the non-equilibrium mode with low tunneling current. The active layer is a short period InAs/GaSb superlattice. Wider bandgap p-type AlSb and n-type InAs layers are used to facilitate the extraction of both electronics and holes from the active layer for the first time. The performance of these devices were compared to the performance of devices grown at the same condition, but without the AlSb barrier layers. The processed devices with the AlSb barrier show a peak responsivity of about 1.2 A/W with Johnson noise limited detectivity of 1.1 X 1011 cm·Hz½/W at 8 μm at 80 K at zero bias. The details of the modeling, growth, and characterizations will be presented. [reprint (PDF)]
 
1.  Continuous-wave room-temperature operation of InGaN/GaN multiquantum well lasers grown by low-pressure metalorganic chemical vapor deposition
M. Razeghi, A. Saxler, P. Kung, D. Walker, X. Zhang, A. Rybaltowski, Y. Xiao, H.J. Yi and J. Diaz
SPIE Conference, San Jose, CA, Vol. 3284, pp. 113-- January 28, 1998 ...[Visit Journal]
Continuous-wave (CW) room temperature operation of InGaN/GaN multi-quantum well (MQW) lasers is reported. Far-field beam divergence as narrow as 13 degrees and 20 degrees for parallel and perpendicular directions to epilayer planes were measured, respectively. The MQW lasers showed strong beam polarization anisotropy as consistent with QW laser gain theory. Dependencies of threshold current on cavity-length and temperature are also consistent with conventional laser theory. No significant degradation in laser characteristics was observed during lifetime testing for over 140 hours of CW room temperature operation. [reprint (PDF)]
 
1.  AlxGa1-xN p-i-n Photodiodes on Sapphire Substrates
D. Walker, P. Kung, P. Sandvik, J. Wu, M. Hamilton, I.H. Lee, J. Diaz, and M. Razeghi
SPIE Conference, San Jose, CA, -- January 27, 1999 ...[Visit Journal]
We report the fabrication and characterization of AlxGa1-xN p-i-n photodiodes (0.05 ≤ to X ≤ 0.30) grown on sapphire by low-pressure metalorganic chemical vapor deposition. The devices present a visible-rejection of about four orders of magnitude with a cutoff wavelength that shifts from 350 nm to 291 nm. They also exhibit a constant responsivity for five decades (30 mW/m² to 1 kW/m²) of optical power density. Using capacitance measurements, the values for the acceptor concentration in the p-AlxGa1-xN region and the unintentional donor concentration in the intrinsic region are found. Photocurrent decays are exponential for high load resistances, with a time constant that corresponds to the RC product of the system. For low load resistances the transient response becomes non-exponential, with a decay time longer than the RC constant. [reprint (PDF)]
 
1.  Compressively-strained multiple quantum well InAsSb lasers emitting at 3.6 μm grown by metal-organic chemical vapor deposition
B. Lane, D. Wu, A. Rybaltowski, H. Yi, J. Diaz, and M. Razeghi
Applied Physics Letters 70 (4)-- January 27, 1997 ...[Visit Journal]
A compressively strained InAsSb/InAs multiple quantum-well (MQW) structure was grown by low-pressure metal-organic chemical vapor deposition. Maximum output power (from two facets) up to 1 W with differential efficiency about 70% was obtained from a MQW laser with stripe width of 100 μm and cavity length of 700 μm for emitting wavelength of 3.65 μm at 90 K in pulse mode operation. About 2 times lower threshold current density was obtained from the MQW lasers for a temperature range of 90 to 140 K compared to the double heterostructure lasers grown on the same growth conditions. [reprint (PDF)]
 
1.  Aluminum nitride films on different orientations of sapphire and silicon
K. Dovidenko, S. Oktyabrsky, J. Narayan, and M. Razeghi
Journal of Applied Physics79 (5)-- March 1, 1996 ...[Visit Journal]
The details of epitaxial growth and microstrictural characteristics of AlN films grown on sapphire (0001), (1012) and Si (100), (111) substrates were investigated using plan‐view and cross‐sectional high‐resolution transmission electron microscopy and x‐ray diffraction techniques. The films were grown by metalorganic chemical vapor deposition using TMA1+NH3+N2 gas mixtures. Different degrees of epitaxy were observed for the films grown on α‐Al2O3 and Si substrates in different orientations. The epitaxial relationship for (0001) sapphire was found to be (0001)AlN∥(0001)sap with in‐plane orientation relationship of [0110]AlN∥[1210]sap. This is equivalent to a 30° rotation in the basal (0001) plane. For (1012) sapphire substrates, the epitaxial relationship was determined to be (1120)AlN∥(1012)sap with the in‐plane alignment of [0001]AlN∥[1011]sap. The AlN films on (0001) α‐Al2O3 were found to contain inverted domain boundaries and a/3〈1120〉 threading dislocations with the estimated density of 1010 cm−2. The density of planar defects (stacking faults) found in AlN films was considerably higher in the case of (1012) compared to (0001) substrates. Films on Si substrates were found to be highly textured c axis oriented when grown on (111) Si, and c axis textured with random in‐plane orientation on (100) Si. The role of thin‐film defects and interfaces on device fabrication is discussed. [reprint (PDF)]
 
1.  High-power laser diodes based on InGaAsP alloys
M. Razeghi
Nature, Vol.369, p.631-633-- June 23, 1994 ...[Visit Journal]
HIGH-POWER, high-coherence solid-state lasers, based on dielectric materials such as ruby or Nd:YAG (yttrium aluminium garnet), have many civilian and military applications. The active media in these lasers are insulating, and must therefore be excited (or ‘pumped’) by optical, rather than electrical, means. Conventional gas-discharge lamps can be used as the pumping source, but semiconductor diode lasers are more efficient, as their wavelength can be tailored to match the absorption properties of the lasing material. Semiconducting AlGaAs alloys are widely used for this purpose, but oxidation of the aluminium and the spreading of defects during device operation limit the lifetime of the diodes3, and hence the reliability of the system as a whole. Aluminium-free InGaAsP compounds, on the other hand, do not have these lifetime-limiting properties. We report here the fabrication of high-power lasers based on InGaAsP (lattice-matched to GaAs substrates), which operate over the same wavelength range as conventional AlGaAs laser diodes and show significantly improved reliability. The other optical and electrical properties of these diodes are either comparable or superior to those of the AlGaAs system. [reprint (PDF)]
 
1.  GaInAsP/InP 1.35 μm Double Heterostructure Laser Grown on Silicon Substrate by Metalorganic Chemical Vapor Deposition
K. Mobarhan, C. Jelen, E. Kolev, and M. Razeghi
Journal of Applied Physics 74 (1)-- July 1, 1993 ...[Visit Journal]
A 1.35 μm GaInAsP/InP double heterostructure laser has been grown on a Si substrate using low‐pressure metalorganic chemical vapor deposition. This was done without the use of a superlattice layer or a very thick InP buffer layer, which are used to prevent the dislocations from spreading into the active layer. Pulsed operation with output power of over 200 mW per facet was achieved at room temperature for broad area lasers with 20 μm width and 170 μm cavity length. The threshold current density of a 350 μm cavity length device was 9.8 kA/cm². The characteristic temperature was 66 K. [reprint (PDF)]
 
1.  High-power InGaAsP/GaAs 0.8 μm laser diodes and peculiarities of operational characteristics
J. Diaz, I. Eliashevich, X. He, H. Yi, L. Wang, E. Kolev, D. Garbuzov, and M. Razeghi
Applied Physics Letters 65 (8)-- August 22, 1994 ...[Visit Journal]
High-power operation of 3 W in pulse mode, 750 mW in quasi-continuous wave and 650 mW in continuous wave per uncoated facet from 100 μm aperture has been demonstrated for 1 mm long cavity InGaAsP/GaAs 808 nm laser diodes prepared by low-pressure metalorganic chemical vapor deposition. Threshold current density of 300 A/cm², differential efficiency of 1.1 W/A, T0=155 °C, transverse beam divergence of 27°, and less than 2 nm linewidth at 808 nm have been measured. No degradation has been observed after 1000 h of operation in a quasi-continuous wave regime. [reprint (PDF)]
 

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