Unstable resonator semiconductor lasers. [GaAs/AlGaAs system]

Thesis/Dissertation · Tue Jan 01 04:00:00 EST 1985

OSTI ID:5971848

Craig, R R

Wet chemical etching was used for the first time to produce unstable-resonator gallium arsenide lasers. These devices use the mode selective property of the resonator to force a broad area (>100 ..mu..m wide) laser to operate in a single lateral and longitudinal mode. Single facet optical powers as high as 400 mW were obtained. The general theory of unstable resonators for laser cavities is presented along with design considerations specific to the GaAs/AlGaAs laser system. Details of the processing steps used to fabricate curved etched mirrors on the semiconductor wafer are given. Results of optical testing indicate that the laser oscillates in a single stable lateral mode as long as the cavity magnification is greater than 3.5. When operating in a single spatial mode the lasers often also emit in a single spectral mode. Tapered devices designed to optimize the differential efficiency at a single facet showed efficiencies as high as 16 W/A. Models for both the threshold current and the differential efficiency agreed well with experimental observations. Finally, new unstable resonator geometries that should further improve the optical properties of this new class of semiconductor lasers are described.

• Research Organization: California Univ., Los Angeles (USA)
• OSTI ID: 5971848
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420300* -- Engineering-- Lasers-- (-1989)
ELECTRONIC EQUIPMENT
EQUIPMENT
FABRICATION
LASERS
OPERATION
OSCILLATIONS
RESONATORS
SEMICONDUCTOR DEVICES
SEMICONDUCTOR LASERS