Spontaneous Synchronization of Transverse Modes in a Quantum-well Laser

Broad-area edge-emitting semiconductor lasers exhibit multiple transverse modes whose nonlinear interaction via the gain medium results in spatio-temporal instabilities [1]. Hence, they are interesting testbeds for studying the dynamics of coupled oscillators. Our experiments demonstrate that groups of lasing modes of a commercial broad-area laser are spontaneously phase locked, while other modes are not locked [2]. The unexpected emergence of groups of synchronized modes coexisting with un synchronized ones is similar to chimera states in systems of coupled oscillators [3].