Optical bistability via coherent and incoherent fields in an Er3+-doped yttrium-aluminum-garnet crystal

We investigated the optical bistability in an Er3+-doped yttrium-aluminum-garnet (YAG) crystal inside a unidirectional ring cavity. We find that the intensity and the frequency detuning of the coherent field as well as the rate of incoherent field can affect the optical bistability dramatically, which can be used to manipulate efficiently the threshold intensity and the hysteresis loop. The effect of the cooperation parameter on the OB is also studied.