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in subjects: "Semiconductor Lasers"

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Manufacturability of vertical-cavity surface emitting lasers grown by organometallic vapor phase epitaxy

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Date: January 1996

Creator: Hou, H. Q.; Chui, H. C.; Hammons, B. E.; Breiland, W. G. & Choquette, K. D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Stimulated emission from semiconductor microcavities

Laser-like emissions from semiconductor microcavities at low temperature have attracted considerable attention recently because of the possibility of realizing a non-equilibrium condensate by using cavity-polaritons. In this paper the authors present experimental studies of optical properties of a microcavity near the lasing threshold. They show that the minimum lasing threshold is achieved when the cavity is tuned significantly below the exciton line center. By comparing emission spectra with … more

Date: April 1, 1997

Creator: Fan, X.; Wang, H.; Hou, H.Q. & Hammons, B.E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Properties of high gain GaAs switches for pulsed power applications

High gain GaAs photoconductive semiconductor switches (PCSS) are being used in a variety of electrical and optical short pulse applications. The highest power application, which the authors are developing, is a compact, repetitive, short pulse linear induction accelerator. The array of PCSS, which drive the accelerator, will switch 75 kA and 250 kV in 30 ns long pulses at 50 Hz. The accelerator will produce a 700 kV, 7kA electron beam for industrial and military applications. In the low power r… more

Date: September 1, 1997

Creator: Zutavern, F. J.; Loubriel, G. M.; Hjalmarson, H. P.; Mar, A.; Helgeson, W. D.; O`Malley, M. W. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Preparation of AlAsSb and Mid-Infrared (3-5 {mu}m) Lasers by Metal-Organic Chemical Vapor Deposition

Mid-infrared (3-5 {mu}m) infrared lasers and LEDs are being developed for use in chemical sensor systems. As-rich, InAsSb heterostructures display unique electronic properties that are beneficial to the performance of these midwave infrared emitters. The authors have grown AlAs{sub 1{minus}x}Sb{sub x} epitaxial layers by metal-organic chemical vapor deposition using trimethylamine (TMAA) or ethyldimethylamine alane (EDMAA), triethylantimony (TESb) and arsine. They examined the growth of AlAs{su… more

Date: December 31, 1996

Creator: Allerman, A. A.; Biefeld, R. M. & Kurtz, S. R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Thermal radiation and conduction in microscale structures. Final report

The general objective of the current research program is to achieve a better understanding of the fundamental mechanisms of thermal radiation and heat conduction in microscale structures commonly encountered in engineering applications. Specifically, the program includes both experimental and analytical investigations of radiative heat transfer in microstructures, conductive heat transfer in micro devices, and short-pulse laser material interactions. Future work is planned to apply the knowledg… more

Date: September 2, 1998

Creator: Tien, C.L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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A Diode Laser System for Synchronous Photoinjection

A laser system, which is composed of a gain switched diode seed laser and a single-pass diode optical amplifier, is used to drive the polarized electron source at Jefferson Lab. The system emits pulsed laser light synchronized to the accelerating cavity radio frequency (rf) at 1497 MHz or the third subharmonic, 499 MHz. The maximum average output power from the laser system is 500 mW and the optical pulse width is 60 to 80 ps. The laser system is compact and very reliable operating remotely for… more

Date: December 31, 1997

Creator: Poelker, M., Hansknecht, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Frequency doubling in poled polymers using anomalous dispersion phase-matching

The authors report on a second harmonic generation in a poled polymer waveguide using anomalous dispersion phase-matching. Blue light ({lambda} = 407 nm) was produced by phase-matching the lowest order fundamental and harmonic modes over a distance of 32 {micro}m. The experimental conversion efficiency was {eta} = 1.2 {times} 10{sup {minus}4}, in agreement with theory. Additionally, they discuss a method of enhancing the conversion efficiency for second harmonic generation using anomalous dispe… more

Date: October 1, 1995

Creator: Kowalczyk, T. C.; Singer, K. D. & Cahill, P. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Vibrational analysis of the elpasolites Cs{sub 2}NaAlF{sub 6} and Cs{sub 2}NaGaF{sub 6} doped with Cr{sup 3+} ions by fluorescence spectroscopy.

Interest in 3d transition metal impurities in ionic crystals has increased due to their important role in the laser activity of these materials. Moreover, recent advances in tunable solid-state lasers and high-power semiconductor laser diode arrays have generated a strong interest in investigating new compounds that emit in the visible and near-infrared spectral regions. In particular, many optical studies have been devoted to Cr{sup 3+}-doped fluoride crystals as a consequence of the high qual… more

Date: September 7, 1999

Creator: Bordallo, H. N.; Sosman, L. P.; Tavares, A. D., Jr. & da Fonseca, R. J. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

InAlGaP vertical cavity surface emitting lasers (VCSELs): Processing and performance

(Al{sub y}Ga{sub 1{minus}y}){sup 1{minus}x}In{sub x}P semiconductor alloys lattice-matched to GaAs are widely used in visible optoelectronic devices. One of the most recent developments in this area is the AlGaInP-based red vertical cavity surface emitting laser (VCSEL). These lasers, which employ AlGaInP active regions and AlGaAs distributed Bragg reflectors (DBRs), have demonstrated continuous-wave (CW) lasing over the 630--690 nm region of the spectrum. Applications for these lasers include … more

Date: June 1, 1997

Creator: Crawford, M. H.; Choquette, K. D.; Hickman, R. J. & Geib, K. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Reduced polarization decay due to carrier in-scattering in a semiconductor active medium

The in-scattering processes, which reduce the decay of the active medium polarization, should be included in a consistent treatment of semiconductor laser gain. The in-scattering processes affect the laser gain by decreasing the influence of the high k-states, which contribute absorption to the spectrum. A theory, based on the semiconductor-Bloch equations with the effects of carrier-carrier scattering treated at the level of the quantum kinetic equations in the Markov limit, predicts gain spec… more

Date: July 1, 1996

Creator: Hughes, S.; Knorr, A.; Koch, S.W. & Chow, W.W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Sensitive detection of tunable diode laser absorption by polarization rotation

Results are presented demonstrating that diode laser absorption sensitivity can be increased by using the Faraday or Kerr effect to rotate the polarization of the source so that crossed polarizers can be used to reduce source noise. The Faraday effect is demonstrated using nitrous oxide in a magnetic field, and the Kerr effect is demonstrated using methyl fluoride in an electric field. Some description of how absorption in an external field causes polarization rotation is presented as well as s… more

Date: January 1, 1985

Creator: Loge, G.W.; Laguna, G.A. & Hartford, A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Photonics at Sandia National Laboratories: From research to applications

Photonics activities at Sandia National Laboratories (SNL) are founded on a strong materials research program. The advent of the Compound Semiconductor Research Laboratory (CSRL) in 1988, accelerated device and materials research and development. Recently, industrial competitiveness has been added as a major mission of the labs. Photonics projects have expanded towards applications-driven programs requiring device and subsystem prototype deliveries and demonstrations. This evolution has resulte… more

Date: February 1, 1994

Creator: Meyer, J.; Owyoung, A.; Zipperian, T. E.; Tsao, J. Y. & Myers, D. R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

High efficiency oxide confined vertical cavity surface emitting lasers

Optical loss is studied in devices with either two aligned apertures above and below the active region or with a single effective aperture above the active region. The latter exhibit slope efficiencies of up to 1 W/A.

Date: August 1, 1995

Creator: Lear, K. L.; Kilcoyne, S. P.; Schneider, R. P., Jr.; Choquette, K. D. & Hadley, G. R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Photonic integrated circuit for all-optical millimeter-wave signal generation

Generation of millimeter-wave electronic signals and power is required for high-frequency communication links, RADAR, remote sensing and other applications. However, in the 30 to 300 GHz mm-wave regime, signal sources are bulky and inefficient. All-optical generation of mm-wave signals promises to improve efficiency to as much as 30 to 50 percent with output power as high as 100 mW. All of this may be achieved while taking advantage of the benefits of monolithic integration to reduce the overal… more

Date: March 1, 1997

Creator: Vawter, G. A.; Mar, A.; Zolper, J. & Hietala, V.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Hydrogen implanted 1.3 {micro}m vertical cavity surface-emitting lasers with dielectric and wafer-boned GaAs/AlAs mirrors

A 1.3 {micro}m wavelength vertical-cavity surface-emitting laser (VCSEL) containing proton implanted isolation regions and a dielectric top mirror and a wafer-bonded GaAs/AlAs bottom mirror was fabricated. A room temperature pulsed threshold current density of 1.13 kA/cm{sup 2} and a threshold current of 2 mA have been demonstrated.

Date: May 1, 1997

Creator: Qian, Y.; Zhu, Z.H.; Lo, Y.H.; Huffaker, D.L.; Deppe, D.G.; Hou, H.Q. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

In-situ spectral reflectance for improving molecular beam epitaxy device growth

This report summarizes the development of in situ spectral reflectance as a tool for improving the quality, reproducibility, and yield of device structures grown from compound semiconductors. Although initially targeted at MBE (Molecular Beam Epitaxy) machines, equipment difficulties forced the authors to test most of their ideas on a MOCVD (Metal Organic Chemical Vapor Deposition) reactor. A pre-growth control strategy using in situ reflectance has led to an unprecedented demonstration of proc… more

Date: May 1, 1997

Creator: Breiland, W.G.; Hammons, B.E.; Hou, H.Q.; Killeen, K.P.; Klem, J.F.; Reno, J.L. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Single transverse mode selectively oxidized vertical cavity lasers

Vertical cavity surface emitting laser (VCSEL) sources have been adopted into Gigabit Ethernet applications in a remarkably short time period. VCSELs are particularly suitable for multimode optical fiber local area networks (LANs), due to their reduced threshold current, circular output beam, and inexpensive and high volume manufacture. Moreover, selectively oxidized VCSELs are nearly ideal LAN sources since the oxide aperture within the laser cavity produces strong electrical and optical confi… more

Date: April 18, 2000

Creator: CHOQUETTE,KENT D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

The technology and applications of selective oxidation of AlGaAs

Wet oxidation of AlGaAs alloys, pioneered at the University of Illinois a decade ago, recently has been used to fabricate high performance vertical-cavity surface emitting lasers (VCSELs). The superior properties of oxide-confined VCSELs has stimulated interest in understanding the fundamental of wet oxidation. The authors briefly review the technology of selective oxidation of III-V alloys, including the oxide microstructure and oxidation processing as well as describe its application to selec… more

Date: August 1, 1998

Creator: Choquette, K. D.; Geib, K. M.; Hou, H. Q.; Mathes, D. & Hull, R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

GaAsSb/InGaAs type-II quantum wells for long-wavelength lasers on GaAs substrates

The authors have investigated the properties of GaAsSb/InGaAs type-II bilayer quantum well structures grown by molecule beam epitaxy for use in long-wavelength lasers on GaAs substrates. Structures with layer, strains and thicknesses designed to be thermodynamically stable against dislocation formation exhibit room-temperature photoluminescence at wavelengths as long as 1.43 {mu}m. The photoluminescence emission wavelength is significantly affected by growth temperature and the sequence of laye… more

Date: March 15, 2000

Creator: Klem, John F.; Spahn, Olga B.; Kurtz, Steven R.; Fritz, Ian J. & Choquette, Kent D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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High-Power Reliable Operation of InGaAsP/InP Laser Bars at 1.73 {micro}m

InGaAsP/InP laser bars with an emission wavelength of 1.73 {micro}m have been fabricated using compressively-strained multiple-quantum-well separate-confinement heterostructures. One-cm-wide, 0.7-fill-factor, diode bars are bonded onto Si microchannel heatsinks. A maximum cw power of 16 W was produced from a one-cm bar. Derated to SW cw, the extrapolated lifetime is 10,000 hours of operation with a 20% degradation in output power. A 10-bar microlensed diode array with a one-square-cm aperture p… more

Date: February 16, 1999

Creator: Skidmore, J.; Page, R. H.; Freitas, B. L.; Reinhardt, C. E.; Utterback, E. J. & Emanuel, M. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

VCSEL applications in sensors and microsystems

Vertical-cavity surface-emitting lasers (VCSELs) are uniquely suited to miniaturized free-space optical systems in which surface-mounting and hybrid assembly techniques can be used to combine different technologies together. Two examples are described of such microsystems that are being developed for sensing applications. The first example is a optical position sensing system for rotating parts. Progress on fabricating similar systems by flip-chip bonding techniques is then discussed. The secon… more

Date: January 1, 1998

Creator: Warren, M. E.; Carson, R. F.; Sweatt, W. C.; Wendt, J. R.; Nevers, J. A.; Crawford, M. H. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Laser chain alignment with low power local light sources

Timely and repeatable alignment of the 192 beam National Ignition Facility (NIF) laser will require an automatic system. Demanding accuracy requirements must be met with high reliability at low cost while minimizing the turnaround time between shots. We describe an approach for internally self-consistent alignment of the mirrors in the laser chains using a network of local light sources that serve as near field and far field alignment references. It incorporates a minimum number of alignment la… more

Date: July 7, 1995

Creator: Bliss, E. S.; Feldman, M.; Murray, J. E. & Vann, C. S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Low-Power Approaches for Parallel, Free-Space Photonic Interconnects

Future advances in the application of photonic interconnects will involve the insertion of parallel-channel links into Multi-Chip Modules (MCMS) and board-level parallel connections. Such applications will drive photonic link components into more compact forms that consume far less power than traditional telecommunication data links. These will make use of new device-level technologies such as vertical cavity surface-emitting lasers and special low-power parallel photoreceiver circuits. Dependi… more

Date: December 31, 1995

Creator: Carson, Richard F.; Lovejoy, Michael L.; Lear, Kevin L.; Warren, Mial E.; Seigal, Pamela K.; Craft, David C. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Exploring New Active Regions for Type 1 InasSb Strained-Layer Lasers

We report on the metal-organic chemical vapor deposition (MOCVD) of mid- infrared InAsSb/InPSb optically pumped lasers grown using a high speed rotating disk reactor (RDR). The devices contain AlAsSb claddings and strained, type 1, InAsSb/InPSb active regions. By changing the layer thickness and composition of InAsSb/InPSb SLSs, we have prepared structures with low temperature (<20K) photoluminescence wavelengths ranging from 3.4 to 4.8 µm. We find a variation of bandgap from 0.272 to 0.3… more

Date: May 13, 1999

Creator: Biefeld, R. M.; Kurtz, S. R. & Phillips, J. D.

Item Type: Article

Partner: UNT Libraries Government Documents Department