C. W. Lowry

High contrast, submilliwatt power InGaAs/GaAs strained‐layer multiple‐quantum‐well asymmetric reflection modulator

A high contrast, low power optical reflection modulator with an InGaAs/GaAs strained‐layer multiple quantum well (MQW) nonlinear spacer is demonstrated. Taking advantage of large absorptive and dispersive nonlinearities near the exciton peak, on/off contrast ratios exceeding 29 dB are achieved with submilliwatt pump powers at room temperature.

Instabilities of a microcavity laser with a weak injected signal

An external cw laser signal in injected into a microcavity laser, and the dynamics of the resulting coupled oscillator system are studied. By variation of the injection detuning and intensity, interesting nonlinear behavior and injection locking are experimentally observed. A theoretical model of this system based on coupled rate equations and including many-body gain effects is presented and yields good agreement with experiment.

Picosecond on‐off switching using a pair of picosecond‐on/nanosecond‐off GaAs étalons

Abstract : Two GaAs etalons, each having a 30 ns recovery time, were connected in series, defining a logic function with a fast turn-on/turn-off time. Applications to routing, multiplexing, data generation and bit permutation are discussed.

Spatial patterns in semiconductor lasers

A beam propagating in a planar waveguide exhibits the characteristics of both a fundamental soliton (little change in waist of a 5-/spl mu/m beam; diffraction is compensated by self-focusing nonlinear refraction) and a second-order soliton (lO-/spl mu/m beam focuses to 3 /spl mu/m with side peaks). Thus a semiconductor gain medium in a planar waveguide is almost ideal for the demonstration of fundamental and second-order spatial solitons; it is even a candidate medium for the formation of a light bullet, i.e., a soliton in space and time.<<ETX>>

Power broadening of coherent energy transfer in semiconductor gain media

Coherent energy transfer gives rise to a new peak and dip in the probe gain spectrum that move proportionally with the intracavity injected power, showing that stimulated emission and absorption significantly speed up the semiconductor response.

Spatial solitary waves, solitons, and vortices

Self-focusing leads to bifurcations of transverse solitary waves in sodium vapor (2D) and to second-order spatial solitons in a GaAs planar waveguide gain medium (1D). Transverse patterns in vertical-cavity surface-emitting lasers are shown to contain field vortices under some conditions. Good agreement is found between experimental data and computations.

Injection-induced instabilities and local gain modification in VCSELs

Injection of a cw narrow-band laser beam into a lasing vertical- cavity surface-emitting laser results in the appearance of new frequencies on the way to injection locking as predicted by our theoretical model. Injection also causes a local asymmetric modification of the lasing line, resulting in a new gain peak at a lower frequency and a dip on the high-frequency side. The peak and dip move out directly as the intracavity injected power, as predicted by our quantum mechanical theory.