The mechanism of mode selection for an external cavity laser

The process of mode hopping between external cavity modes of a laser diode with optical feedback is described by analogy with noise driven transitions of a particle between potential valleys. The model explains why the dominant mode is the mode with the lowest linewidth and not the mode with the lowest carrier density. It also gives a simple analytic expression for the rate of mode hopping. The expression is shown to predict the results of computer simulations to a good approximation.<
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