Observation of supermodes in a phase-locked diode laser array

Abstract

Phase-locked diode laser arrays have been observed to oscillate in collective modes (supermodes) characteristic of a composite waveguide formed as a result of optical coupling between the fields of individual waveguides in the array. For an array of 11 gain-guided lasers, as many as five different supermodes oscillated simultaneously at wavelengths separated by approximately 0.3 Å. Each supermode was identified by spectrally resolving the spatial profile of the optical intensity on the laser facet.