二维超快量子相干光谱仪研制

Recent researches have suggest that high-order quantum correlation in ultrafast scale is essential for the properties in various material systems including semiconductors, polymers, photosynthesis complexes, and etc. High-order quantum correlation has become a cutting edge scientific problem in the emerging subjects of quantum information, quantum chemistry, and quantum biology. Most of these studies rely on the precise technique of multidimensional coherent spectroscopy. In this project, we propose to construct an equipment of two-dimensional ultrafast quantum coherent spectrometer (2D-UQCS) suitable for general investigation on the quantum correlation. The 2D-UQCS will consist of several modules with independent functions. Precise and cost-effective modules including fast feedback loop, motor-controlled wedge pairs, and two-dimensional spatial light modulator will be integrated to address the issues of mechanical drift, sub-femtosecond optical delay, and pulse shaping. To enlarge the scope of application, we develop accessory of noncollinear optical parametric amplifier for sub-35 femtosecond pulses with tunable wavelength from visible to near infrared range. 2D-UQCS will serve as a general ultrafast characterization platform that will make it much easier to investigate the ultrafast quantum correlation. This equipment can help the community in China to do cutting edge research and make original innovations.

近年来研究表明超快时间尺度的高阶量子相干效应在包括半导体、聚合物和光合作用体系等多种材料系中发挥着关键性的作用，相关研究也成为量子信息、量子化学、量子生物学等新学科分支前沿研究的重要问题，而这些问题的研究依赖于精密的多维相干光谱技术。本项目将结合申请人在领域内二十多年的工作经验，致力于开发一套适用于超快量子相干特性研究的二维超快量子相干光谱仪。该仪器将采用模块化设计，利用先进经济的快速反馈回路、电控锲形镜对以及二维光调制器来实现精密的空间矫正，时间延迟以及脉冲整形，并采取外差检测方法实现精密微弱相干信号的检测和分析。为进一步提高仪器的适用范围，一并开发非共线光学参量放大技术，拓展超快脉冲波长范围，压缩脉冲宽度。该仪器的成功开发，有望成为一套拥有自主产权的超快光谱学平台，突破超快相干特性前沿研究的技术壁垒，有利于中国开展相关领域的原始创新，并大大改善目前国内超短脉冲激光器使用效率较低的现状。

二维光谱仪是近年发展的可直接检测能级跃迁的量子相干作用的设备，能提供传统光谱仪无法测试的相位信息。受制于相位锁定的技术限制，目前商业公司的二维光谱仪只覆盖中远红外波段，尚无适用于电子能级研究的商用近红外可见波段的二维光谱仪。本项目研制二维傅里叶电子光谱仪,实现超高时间分辨下的可见波段的二维光谱仪，我们搭建了非共线光学参量放大装置，以此为超短脉冲光源(<10 fs),结合锲形镜对巧妙的实现脉冲间的位相锁定，实现项目预期的非共线四波混频二维光谱仪，完成了各项测试，设计指标均以达成；在此基础我们进一步探索了利用瞬态吸收装置，实现双色的二维光谱，并结合主动锁相装置，成功实现部分共线的二维量子相干光谱仪。完成的二维光谱仪已经成功利用到科研项目，在半导体量子点、有机材料单线态分裂等项目的研究中扮演了重要角色。