Nonlinear dynamics of a quantum cascade laser with tilted optical feedback

Abstract

Interband semiconductor lasers subject to optical feedback usually produce rich nonlinear dynamics. However, it is hard to destabilize quantum cascade lasers using common optical feedback, because of its ultrashort carrier lifetime and small linewidth broadening factor. In this work, we show that optical feedback with a tilted angle can destabilize quantum cascade lasers, which produce three types of nonlinear dynamics. We observe periodic oscillations with small tilted angles, quasiperiodic oscillations with moderate angles, and low-frequency oscillations with large angles, respectively. In contrast, this type of dynamics does not occur with well-aligned optical feedback.