A METHOD FOR PRODUCING AN EXTERNALLY INJECTED GAIN SWITCH LASER ULTRASHORT PULSE

摘要

A method for producing an externally injected gain switch laser ultrashort pulse, comprising following steps: ultrashort light pulse signals having mutli-longitudinal mode characteristic produced by the gain switch laser are inputted into an optical amplifier and then amplified; a spectral component signal selector selects a narrow spectral component signal outputted by the optical amplifier, the narrow spectral component signal is within a amplified spontaneous emission noise frequency band and its central wavelength is equal to one longitudinal mode of the gain switch laser; a route of the narrow spectral component signal is used as an external seed light and reinjected into the gain switch laser via a spectral component signal feedback loop. Therefore the oscillation of a selected single longitudinal mode within the cavity of the gain switch laser is enhanced, thereby forming an externally light injected locking. Another route of the narrow spectral component signal is used as a required ultrashort pulse.