T. J. Rotter

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An alternative segmented-contact method for accurate measurement of the optical gain and absorption of quantum-dot and quantum-dash active materials with small optical gain is reported. The usual error from unguided spontaneous emission is reduced by subtracting signals acquired from three independently controlled sections as opposed to just two found in(More)
We assess the influence of the degree of quantum confinement on the carrier recovery times in semiconductor optical amplifiers (SOAs) through an experimental comparative study of three amplifiers, one InAs-InGaAsP-InP quantum dot (0-D), one InAs-InAlGaAs-InP quantum dash (1-D), and one InGaAsP-In-GaAsP-InP quantum well (2-D), all of which operate near(More)
In this letter, we report the fabrication and characterization of self-aligned inversion-type enhancement-mode In<sub>0.53</sub>Ga<sub>0.47</sub>As metal-oxide-semiconductor field-effect transistors (MOSFETs). The In<sub>0.53</sub>Ga<sub>0.47</sub>As surface was passivated by atomic layer deposition of a 2.5-nm-thick AIN interfacial layer.(More)
We report an InAs quantum dot-based optically pumped vertical external-cavity surface-emitting laser (VECSEL), with a continuously variable emission wavelength from 1220 to 1280 nm through the use of epitaxial gradient across the wafer. We demonstrate the performance of two designs of this VECSEL. The first design, 4 &#x00D7; 3, makes use of a resonant(More)
We report time-resolved measurements of the linewidth enhancement factors (-factors) , and , associated with the adiabatic carrier recovery, carrier heating, and two-photon absorption dynamical processes, respectively, in semiconductor optical amplifiers (SOAs) with different degrees of dimensionality-one InAs/InGaAsP/InP quantum dot (0-D), one(More)
Wavelength up-conversion of 1.6-ps pulses is achieved through four-wave mixing (FWM) in an InAs-InP quantum-dash ridge waveguide laser operating at 1587 nm. The up-conversion efficiency is measured as a function of injection current, for pump-probe detunings in the range 1.8-3.8 THz. The efficiency is found to increase with current up to a point of(More)
We report the growth of optically pumped vertical-external-cavity surface-emitting lasers (VECSELs) based on InGaSb/AlGaSb quantum wells grown on GaAs/AlGaAs distributed Bragg reflectors (DBRs). The 7.78% lattice mismatch between GaSb and GaAs is accommodated by an array of 90&#x00B0; misfit dislocations at the interface. This results in spontaneous(More)
M. P. Hasselbeck, D. Stalnaker, L. A. Schlie, T. J. Rotter, A. Stintz, and M. Sheik-Bahae USAF Research Laboratory, Directed Energy Directorate, Kirtland AFB, New Mexico 87117 Department of Physics and Astronomy, University of New Mexico, Albuquerque, New Mexico 87131 Center for High Technology Materials, University of New Mexico, Albuquerque, New Mexico(More)