CAJ | 학술논문

在碘蒸气中研究了染料激光稳定性对简并四波混频(DFWM)信噪比的影响.实验中采用多模Nd:YAG激光器倍频的输出泵浦染料激光器(染料PM580溶于酒精).在具有前向补偿分光系统和图像探测系统的帮助下,在常温常压条件下测得泵浦光在波长为554.013 nm时达到饱和光强为290 μJ.同时发现染料激光器的光稳定性(输出波长范围,光束质量和能最转换效率等)随使用时间,泵浦激光脉冲次数和能量的增加而逐渐减弱.另外通过对比发现在染料激光器输出不稳定时,光源单色性和指向性等指标的变化导致在同一泵浦强度不同时刻获得的DFWM信号强度相差很大,且DFWM信号信噪比低.染料激光器光源稳定性对DFWM信号影响的研究结果对物质的痕迹量探测以及无荧光物质光谱定标等方面的应用具有重要意义.
재전증기중연구료염료격광은정성대간병사파혼빈(DFWM)신조비적영향.실험중채용다모Nd:YAG격광기배빈적수출빙포염료격광기(염료PM580용우주정).재구유전향보상분광계통화도상탐측계통적방조하,재상온상압조건하측득빙포광재파장위554.013 nm시체도포화광강위290 μJ.동시발현염료격광기적광은정성(수출파장범위,광속질량화능최전환효솔등)수사용시간,빙포격광맥충차수화능량적증가이축점감약.령외통과대비발현재염료격광기수출불은정시,광원단색성화지향성등지표적변화도치재동일빙포강도불동시각획득적DFWM신호강도상차흔대,차DFWM신호신조비저.염료격광기광원은정성대DFWM신호영향적연구결과대물질적흔적량탐측이급무형광물질광보정표등방면적응용구유중요의의.
The effects of the stability of dye laser on the signal to noise ratio in degenerate four-wave mixing(DFWM)were first investigated in iodine vapor using forward geometries.Frequency-doubled outputs from a multi-mode Nd:YAG laser pumped dye laser with laser dye PM580 dissolved in ethanol was used.With the help of forward compensated beam-split technique and imaging detecting system,the saturation intensity of DFWM spectrum in the iodine vapor at 5 554.013 nm was first measured to be 290 μJ under the condition of atmospheric pressure and room temperature.The features of the dye laser such as wavelength ranges,beam quality and energy conversion efficiency decreased gradually with increasing pumping service use,pulse number and intensity.Additionally,with the comparison of the stable and unstable dye laser output,it was found that the instability of dye laser output had greatly influenced the DFWM signal and decreased the signal to background noise ratio.Shot to shot jitter and the broadening in the output frequency leads to an effective broadening of the recorded spectrum and loss of the DFWM signal to noise ratio under the same pumping intensity at different time.The study is of importance to the detection of trace atom,molecule and radical in combustion diagnosis.