CAJ | 학술논문

设计了一个表征样品非线性特性的基于虚拟仪器的z扫描实验系统。利用Labview控制数字示波器TDS3012采集两路光强信号，并结合对微位移平台的控制实现Z扫描。以Nd：YAG飞秒放大器产生的800nm的飞秒激光作为探测光，经透镜聚焦后通过薄介质样品；用数字示波器测量样品在透镜焦点附近的透射光强，经过数据处理得到样品的非线性折射率和非线性吸收系数。利用该实验系统，对标准非线性吸收样品Rhodamine 6B进行了测量，计算得到其双光子吸收截面为σ^2=6．8GM（GM：10^-50cm4s photon^-1 molecule^-1），该结果与其他文献利用不同测量方法得到的结果接近，证明该实验系统的测量结果是正确的，可满足非线性测量的精度要求。
설계료일개표정양품비선성특성적기우허의의기적z소묘실험계통。이용Labview공제수자시파기TDS3012채집량로광강신호，병결합대미위이평태적공제실현Z소묘。이Nd：YAG비초방대기산생적800nm적비초격광작위탐측광，경투경취초후통과박개질양품；용수자시파기측량양품재투경초점부근적투사광강，경과수거처리득도양품적비선성절사솔화비선성흡수계수。이용해실험계통，대표준비선성흡수양품Rhodamine 6B진행료측량，계산득도기쌍광자흡수절면위σ^2=6．8GM（GM：10^-50cm4s photon^-1 molecule^-1），해결과여기타문헌이용불동측량방법득도적결과접근，증명해실험계통적측량결과시정학적，가만족비선성측량적정도요구。
A sensitive Z-scan measurement system using a femtosecond Nd: YAG laser(800 nm) as the excited light and based on Labview is reported. Under the control of Labview, the digital oscilloscope TDS3012 and the micro-translation stage are used to measure the light intensity, and the Z-scan function is realized. By tak- ing a 800 nm fs laser from a Nd: YAG fs amplifier as a detecting light, the two transmittance intensities of light is measured by passing it through a thin nonlinear sample with a digital oscilloscope. Then both the nonlinear refractive index and nonlinear absorption coefficient can be obtained. The nonlinear absorption coefficient of Rhodamine 6B at 800 nm was measured. The results produced a two-photon absorption cross-section of 6. 8 GM( GM = 10^-50 cm^4 s photon^-1 molecule^-1 ). The system is shown to be reliable by comparison of our meas- ured results with the those obtained from other different measuring methods.