Burrell E. Hammons

Resonant periodic gain surface-emitting semiconductor lasers

A surface-emitting semiconductor laser structure with a vertical cavity, extremely short gain medium length, and enhanced gain at a specific design wavelength is described. The active region consists of a series of quantum wells spaced at one half the wavelength of a particular optical transition in the quantum wells. This special periodicity allows the antinodes of the standing-wave optical field to coincide with the gain elements, enhancing the frequency selectivity, increasing the gain in the vertical direction by a factor of two compared to a uniform medium or a nonresonant multiple quantum well, and substantially reducing amplified spontaneous emission. Optically pumped lasing was achieved in a GaAs/AlGaAs structure grown by molecular-beam epitaxy, with what is believed to be the shortest gain medium (310 nm) ever reported. >

Wavelength-resonant, Surface-emitting Semiconductor Laser: A Novel Quantum Optical Structure

Wavelength-Resonant, Surface-Emitting Semiconductor Laser: A Novel Quantum Optical Structure M.Y.A. Raja, S.R.J. Brueck, M. Osinski, C.F. Schaus, J.G. Mclnerney, University of New Mexico, Albuquerque, NM and T.M. Brennan, B.E. Hammons, Sandia National Laboratories, Albuquerque, NM. We designed, fabricated and demonstrated lasing action in a novel vertical surface-emitting laser structure. The MBE-grown structure is a seriesof 10-nm thick GaAs quantum wells separated by 120-nm thick AlGaAs barriers for a spatially periodic gain medium resonant with the lasing wavelength. Lasing has been achieved by optical pumping with a gain length of only 320 nm.

Comparison of Low Temperature Photoluminescence of Bulk MBE Grown AlGaAs and GaAs Using a Graphite Generated Dimerb Versus a Standard Tetramer Arsenic Group-V Source

The carbon concentrations in GaAs and AIGaAs grown by Molecular Beam Epitaxy (MBE) have been studied when a graphite generated dimeric arsenic species and a standard tetramer arsenic species are used as the group-V source. Photoluminescence and Van der Pauw-Hall measurements have been made to examine the material quality in reference to which arsenic species is used for film growth. Results indicate that a graphite crucible arrangement for the thermal cracking of As 4 produces significant carbon contamination and is unacceptable for the MBE growth of GaAs and AlGaAs.