Lateral and longitudinal mode discrimination in index-guided circular ring semiconductor lasers

We present the first analysis of the mode structure and thresholds of index-guided ring lasers, and on longitudinal mode discrimination of X-junction-coupled ring lasers. Submilliampere thresholds can be achieved with single-lateral-mode ring lasers having small refractive index steps. In addition, strong longitudinal mode discrimination can be obtained with ring lasers of different cavity lengths coupled via an X junction.<
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