We investigate the total intensity fluctuation spectrum of the two-longitudinal- mode Nd:YVO4microchip laser(ML).We find that low-frequency relaxation oscillation(RO) peaks still appear in the total intensity flu...We investigate the total intensity fluctuation spectrum of the two-longitudinal- mode Nd:YVO4microchip laser(ML).We find that low-frequency relaxation oscillation(RO) peaks still appear in the total intensity fluctuation spectrum, which is different from a previous research result that the low-frequency RO peaks exist in the spectrum of the individual mode but compensate for each other totally in the total intensity fluctuation spectrum. Taking the spatial hole-burning effect into account, one and two-mode rate equations for Nd:YVO4ML laser are established and studied. Based on the theoretical model, we find that when the gains and losses for two longitudinal models are different, a low-frequency RO peak will appear in the total intensity fluctuation spectrum, while when they share the same gain and loss, the total spectrum will behave like that of a single mode laser. Theoretical simulation results coincide with experimental results very well.展开更多
基金Project supported by the Beijing Higher Education Young Elite Teacher ProjectChina(Grant No.YETP0086)+2 种基金the Tsinghua University Initiative Scientific Research ProgrammeChina(Grant No.2012Z02166)the Special-funded Programme on National Key Scientific Instruments and Equipment Development of China(Grant No.2011YQ04013603)
文摘We investigate the total intensity fluctuation spectrum of the two-longitudinal- mode Nd:YVO4microchip laser(ML).We find that low-frequency relaxation oscillation(RO) peaks still appear in the total intensity fluctuation spectrum, which is different from a previous research result that the low-frequency RO peaks exist in the spectrum of the individual mode but compensate for each other totally in the total intensity fluctuation spectrum. Taking the spatial hole-burning effect into account, one and two-mode rate equations for Nd:YVO4ML laser are established and studied. Based on the theoretical model, we find that when the gains and losses for two longitudinal models are different, a low-frequency RO peak will appear in the total intensity fluctuation spectrum, while when they share the same gain and loss, the total spectrum will behave like that of a single mode laser. Theoretical simulation results coincide with experimental results very well.