학술논문

基于泵浦强度调制的超快光纤激光器中孤子分子光谱脉动动力学研究 / Spectral pulsation dynamics of soliton molecules in ultrafast fiber lasers based on pump intensity modulation
Document Type
Academic Journal
Source
物理学报 / Acta Physica Sinica. 73(1):87-93
Subject
孤子分子
泵浦强度调制
光谱脉动
色散傅里叶变换
soliton molecule
pump intensity modulation
spectral fluctuation
dispersive Fourier transform
Language
Chinese
ISSN
1000-3290
Abstract
采用实时傅里叶变换光谱探测技术,研究了基于泵浦强度调制的超快掺铒光纤锁模激光器中孤子分子光谱的脉动动力学.结果表明,在一定的泵浦强度调制情况下,孤子分子光谱的脉动周期可由泵浦调制频率进行调控.同时,孤子分子脉动幅度以及孤子间相对相位的演化与泵浦调制频率有关.在较低的调制频率(如1 kHz)下,光谱脉动的孤子分子内脉冲间的相对相位随传播时间呈现滑动型动力学.随着调制频率逐渐加大(如 20 kHz),孤子分子内脉冲间的相对相位演化逐渐趋于混乱,表明脉动孤子分子可能存在固有的共振频率,与孤子分子的稳定性有关.研究结果对于深入理解孤子分子的产生与稳定性提升、孤子分子的全光操作及应用具有重要的指导意义.
This study employs real-time Fourier transform spectroscopy to investigate the pulsation dynamics of soliton molecules in a mode-locked erbium-doped fiber laser,by modulating pump intensity.By controlling the driving voltage of the pump source,we systematically observe and characterize the influence of external modulation signals on the amplitude,period,pulsation frequency,and the relative phase evolution among the pulsating soliton molecules in their spectra. The results demonstrate that under specific conditions of pump intensity modulation,the pulsation period of soliton molecule spectra can be precisely regulated by the pump modulation frequency.At the same time,the amplitude of soliton molecule pulsations and the evolution of relative phase among the solitons are intricately tied to the pump modulation frequency.At lower modulation frequencies,such as 1 kHz,the relative phase among the pulses in the soliton molecule exhibits a sliding-type dynamics as a function of propagation time. As the modulation frequency gradually increases to 5 kHz,a scenario emerges where three soliton molecules are generated.Notably,both the soliton spacing and relative phase undergo synchronous adjustments influenced by the pump modulation.With the modulation frequency further increasing,say,to 20 kHz,the relative phase evolution among the pulses within the soliton molecule gradually descends into chaos.This observation suggests the plausible existence of an inherent resonant frequency associated with pulsating soliton molecules,which has direct implications for their stability. The findings of this research are of significance in advancing our comprehension of soliton molecule generation and enhancing their stability.In addition,they provide valuable insights into the broader domain of all-optical manipulation and applications of soliton molecules,and their application in pulse encoding in mode-locked laser systems.