Towards Generation of Indistinguishable Coherent States

We have addressed the characteristic distinguishability of coherent states in the temporal domain from a directly modulated quantum well-based gain-switched laser diode. Using small-signal and large-signal models, we identify tunable parameters to generate indistinguishable coherent states from an electrically pumped semiconductor laser. The experiment confirms the generation of indistinguishable signal and decoy coherent states as predicted by the numerical simulation.