Tunable coupled-cavity semiconductor laser based on a half-wave bow-tie coupler.

We propose and experimentally demonstrate a widely tunable coupled-cavity semiconductor laser based on a novel half-wave bow-tie coupler. The laser comprises two resonate cavities connected through the bow-tie coupler consisting of two back-to-back corner reflectors connected with a short waveguide, which produces a half-wave cross-coupling phase with an optimum coupling coefficient for achieving high mode selectivity. No complex grating or multiple epitaxial growth is needed. By tuning a single electrode at a fixed temperature, 29.6 nm wavelength tuning covering 38 channels with 100 GHz frequency spacing is achieved experimentally, with a side-mode suppression ratio of over 35 dB.

All-optical flip-flop operation based on bistability in V-cavity laser.

We theoretically analyzed and experimentally demonstrated an injection-locking based all-optical flip-flop memory using a simple and compact tunable V-cavity laser (VCL). A bistable region in the tuning characteristics of the VCL is employed for the flip-flop operation. The state of the VCL can be set and reset by injecting signal pulses at two different wavelengths. The pulse power for both set and reset signal is only about 1 pJ. Short response times of about 150 ps are measured for storing and erasing.