Quantum Cascade Limaçon-Shaped Micro-Cavity Lasers and Their Array Device

The micro-disk cavity laser with whispering gallery mode (WGM) has unique advantages such as small mode volume, low threshold, high-quality factor Q and ease of fabrication. They are expected to be used into optoelectronic integration and optical communication. To further play the advantages of the micro-disk cavity laser in the field of optoelectronic integration, the micro-cavity laser should not only have good directional output characteristics, but also have higher optical output power. Therefore, in this paper, quantum cascade (QC) directional-emitting micro-cavity lasers with improved light output power character were demonstrated. In the experiment, we used InP-based GaInAs/AlInAs QC laser material to fabricate micro-cavity lasers with different device sizes and investigated their optical output properties such as light output power, threshold current, and far-field distribution. The test results show that both the output power and threshold current of the device increase with the increase of the device size. The device with a large device size of 150 μm produced a peak power of about 15 mW. In order to further improve the light output power of the micro-cavity laser, a micro-cavity laser array with an array period of 600 μm was finally fabricated, and the light output power was significantly improved.