All-fiber ring soliton laser mode locked with a nonlinear mirror

An amplifying nonlinear-optical fiber loop mirror is used as the gain element in an all-fiber ring laser. The resulting double-loop structure resembles a figure eight. The output of the amplifying nonlinear-optical fiber loop mirror is fed back to the input through an optical isolator to ensure unidirectional operation. The laser produces 2-ps transform-limited pulses. The pulse energy corresponds to that of the fundamental soliton in the fiber used.