Modal competition via four-wave mixing in single-mode extended-cavity semiconductor lasers

An analysis of the wave-coupling phenomena in extended-cavity semiconductor lasers is carried out to investigate the conditions of mode-hop-free single-mode operation. Taking into account the external cavity selectivity and the mode coupling via four-wave mixing in the active medium, we present a theoretical analysis of the modal competition and perform calculations that are in good agreement with experimental results obtained with a 1.55-/spl mu/m extended-cavity laser.