GaAlAs buried multiquantum well lasers fabricated by diffusion-induced disordering

A new transverse-mode-controlled laser called a buried multiquantum-well (BMQW) laser has been developed. In order to make it possible to bury the MQW laser active region utilizing the diffusion-induced disordering (DID) of GaAs-GaAlAs MQW, zinc was selectively diffused into the MQW structure, resulting in a 3–8-μm-wide stripe region. The threshold current is as low as 33 mA with a 300-μm cavity length and a fundamental transverse mode can be achieved. As a result of studying the relation of the waveguide geometry to the longitudinal and transverse modes it was concluded that this BMQW laser made by a simple DID process acts as an index-guided laser.