Bandgap-Engineered Broadband Stimulated Emission in Semiconductor Quantum Dash Interband Laser

Authors demonstrate the generation of broadband stimulated emission in the postgrowth wavelength tuned InAs/InAlGaAs quantum-dash (Qdash) laser grown on InP substrate. The laser exhibits room temperature lasing wavelength coverage of up to 50 nm at center wavelength of ~1.57 mum. Despite the bandgap blue-shift of ~70 nm after Qdash intermixing process, the laser exhibits a broadband signature of lasing linewidth, which is comparable to the as-grown laser. The integrity of the material is retained after intermixing, suggesting its potential application in the fabrication of monolitically-integrated ultra-broadband semiconductor Qdash laser.