Towards Generation of Indistinguishable Coherent States

TL;DR

This paper demonstrates how to generate indistinguishable coherent states from a gain-switched laser diode using models and experiments, which is crucial for quantum communication security.

Contribution

It introduces a method to produce indistinguishable coherent states from a directly modulated semiconductor laser, validated through modeling and experimental confirmation.

Findings

Successful generation of indistinguishable coherent states

Modeling aligns with experimental results

Tunable parameters identified for state indistinguishability

Abstract

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.