强散射介质中0π脉冲的受激拉曼光谱  

Stimulated Raman spectroscopy of 0π pulse in strongly scattering media

作　　者：孙栋 Dhayal Suman 林洪沂 Rostovtsev Yuri SUN Dong;DHAYAL Suman;LIN Hongyi;ROSTOVTSEV Yuri(Fujian Provincial Key Laboratory of Optoelectronic Technology and Devices,School of Optoelectronic andCommunication Engineering,Xiamen University of Technology,Xiamen 361024,China;Center for Nonlinear Sciences,Department of Physics,University of North Texas,Denton,TX 76203,USA)

机构地区：[1]厦门理工学院光电与通信工程学院,福建省光电技术与器件重点实验室(厦门理工学院),福建厦门361024 [2]北德州大学物理系,北德州大学非线性科学中心,德克萨斯州,登顿TX76203

出　　处：《厦门大学学报（自然科学版）》2019年第3期402-407,共6页Journal of Xiamen University：Natural Science

基　　金：美国国家自然科学基金(PHY-1241032,EEC-0540832,PHY-1068554);福建省自然科学基金(2018I0019,2016J01683)

摘　　要：拉曼光谱由于具有响应速度快,灵敏度高,不侵入待测物质等特点,近年来在生物和医学检测及成像领域的应用受到了较多的关注.然而,生物活组织往往具有较强的散射特性,影响受激拉曼光谱的成像质量.为了提高受激拉曼光谱的成像质量,引入脉冲波形技术,采用对拉曼散射具有较高敏感性的0π脉冲为斯托克斯脉冲,利用离散偶极矩近似方法,对强散射介质中的脉冲传输进行数值模拟.研究发现:在多次散射的作用下,尽管激光脉冲强度随着其在介质中的传输距离增大而衰减,但受益于0π脉冲的特性,输出信号在双光子共振时的强度将增强2倍左右,为提高强散射介质中的受激拉曼光谱质量提供了一个新的可能.Due to its fast response,high sensitivity,and non-intrusion into the sample,the application of Raman spectroscopy in the biological and medical detection and imaging fields has received much attention in recent years.However,biological living tissues usually exhibit high scattering characteristics,which greatly limit the imaging quality of stimulated Raman spectroscopy.To improve the imaging quality,we study the propagation of pulses and stimulated Raman spectroscopy process in strong scattering media by using the pulse shaping technique and discrete dipole moment approximation method,in which a 0-pi pulse with high sensitivity to Raman scattering is adopted as Stokes pulse.It is found that under the influence of multiple scattering,the pulse intensity decreases with the increase of its propagation distance in the media.Benefiting from these characteristics of 0π pulse,the intensity of output signal in two-photon resonance increases by approximately three times,providing a possible way to improve the imaging quality of stimulated Raman spectroscopy in strong scattering media.

关 键 词：受激拉曼光谱 相干散射 脉冲波形 离散偶极近似 

分 类 号：O431.2[机械工程—光学工程] O437.3[理学—光学]