A single-directional microcavity laser with microloop mirrors and widened medium realized with quantum-well intermixing

We describe a linear-geometry microcavity laser with microloops as end reflectors to achieve single-directional output. Finite-difference time-domain simulation is used to optimize the microloop mirror (MLM) performance and simulate the laser operation. We show that a single-directional microlaser with cavity length as small as 25 μm can be realized. A method to obtain higher output power from the microlaser with widened gain medium (WGM) is discussed. An initial fabrication of the MLM-WGM laser with transparent MLM formed by quantum-well intermixing is presented. A low-lasing threshold of /spl sim/0.4 mA is achieved.