Polarization insensitive 40 GHz self-pulsating DBR lasers with enhanced nonlinearities and wide self-pulsation frequency tunability

40 GHz self-pulsating distributed Bragg reflector lasers with a polarization insensitive bulk active layer of 0.7×0.5 μm2 showed enhanced non-linear behavior at low power level, and nearly 1 GHz of continuous self-pulsation frequency tunability using two active sections.