Third-order nonlinearity induced lateral-mode frequency locking and beam instability in the high-power operation of narrow-ridge semiconductor lasers

Lateral-mode frequency locking in the high-power operation of narrow-ridge semiconductor lasers is shown to be attributable to carrier-induced third-order nonlinearities. Not only are known experimental characteristics of beam steering explained with this theory, but new insights into the nature of beam steering, such as its inherent bistable behavior, are obtained.