Dynamics of broad area diode lasers with phase conjugate feedback

Abstract

The current work presents an experimental investigation of the dynamic behaviour of an 800 nm, 500 mW broad area diode laser subject to phase conjugate feedback. The phase conjugation is achieved with a barium titanate crystal in a self-pumped internal reflection geometry. The observed results are compared to the behaviour of the broad area diode laser subject to conventional optical feedback (from a plane mirror) and to an 850 nm 50 mW single mode diode laser subject to phase conjugate (and conventional optical) feedback. It is found that the range of feedback fractions that produce a dynamically unstable output power is distinct for each of these cases. Additionally, characteristics of the transition into dynamic instability are different for each case. The relevance of existing theories to the current experimental observations is discussed.