Bit correlation and memory effects in high-speed pump modulation of a fiber laser

In the context of optical communications, we study experimentally the behavior of a pump-modulated fiber laser at frequencies close to the relaxation oscillation frequency. We show that correlations can appear between successive "1" bits in various situations. This "memory effect" can be interpreted using a simple deterministic model, and we show that this effect is related to the behavior of the population inversion, which does not follow adiabatically the photon number. Our results also suggest the existence of an optimum pump bias value for optical communications, slightly below threshold.<
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