Bridge-contact microdisk lasers formed by wet chemical etching

Presents an approach to create quantum dot microlasers on GaAs substrates with a disk cavity, a bridge-type electrical contact and a supporting mesa formed by wet chemical etching. The bridge structure consists of two mesa structures connected by a suspended gold beam, one of which is actually a microdisk cavity, and the other allows to create an external electrical contact. The proposed method opens up ways to fabricate small-diameter injection microlasers, since it eliminates the need to attach an electrical wire to the upper surface of the microlaser cavity. Microlasers with a bridge electrical contact were fabricated, the formation of a close-to-vertical microcavity side-wall in the active region of the structure was demonstrated and the electroluminescence spectra of the microlasers were obtained in a wide range of pump currents, confirming the possibility of lasing both at room and elevated temperatures.