Abstract

Optical injection is a process in which light from one laser is injected into the cavity of another known as the slave. The system may be modelled using standard rate equations for the electric field and the carrier density and numerical simulations of these equations have shown excellent agreement with experiments [1] (and references therein). However, the equations are complicated and analytic results are rare. We consider this system for low injection levels and derive a single, third-order equation for the phase of the electric field which depends on three important laser parameters: the linewidth enhacement factor α, the relaxation oscillation (RO) frequency and the RO damping factor Γ. It is a significant simplification of the full model conceptually and crucially allows analytical results which are experimentally accessible. A similar equation was derived previously [2], which reproduced some properties of the system well but failed to capture features associated with Hopf bifurcations predicted by the full set of equations.

© 2009 IEEE