Self-consistent theory of locking of coupled semiconductor lasers

In coupled lasers the effective coupling depends on the individual inversions in each constituent laser. Therefore, locking of coupled lasers defines a nonlinear problem that requires self-consistent treatment. Here we report on a general study of the frequency locking of two Fabry-Perot lasers using a self-consistent rate-equation approach. Application of the theory to the coupled cavity quantum-well semiconductor lasers of D’Agostino et al. [Optics Letters 40 (2015) 653] yields very good agreement with measurements.