论文标题
超快极化调节瞬态光谱学研究了溶液和细胞中电子激发态动力学
Ultrafast polarization-modulation transient spectroscopy to study electronic excited state dynamics in solutions and cells
论文作者
论文摘要
已经开发了一种新型的极化调节方法，用于研究多原子和生物学相关分子的电子激发态在激发秒激光脉冲下的快速各向异性弛豫。该方法基于使用光弹性调制器对泵束极化的调节，并通过高度敏感的解调平衡方案来检测对瞬态信号的各向异性贡献。该方法在辅助酶NADH（烟素 - 氨基二核苷酸）的水溶液上测试，在360 nm处泵送，并在720 nm处进行探测。在亚平时域中已经观察到各向异性振动松弛和旋转扩散。该方法显着提高了瞬态测量的准确性，并允许在低能（A NJ）泵脉冲处记录高质量信号。
A novel polarization-modulation transient method has been developed for studying fast anisotropic relaxation in electronic excited states of polyatomic and biologically relevant molecules under excitation with femtosecond laser pulses. The method is based on the modulation of pump beam polarization with a photo-elastic modulator and detection of an anisotropic contribution to the transient signal by a highly-sensitive demodulation balanced scheme. The method was tested on aqueous solution of coenzyme NADH (nicotin-amideadenine-dinucleotide) pumped at 360 nm and probed at 720 nm. Anisotropic vibrational relaxation and rotational diffusion have been observed in the subpicosecond time domain. The method significantly enhances the accuracy of transient measurements and allows for recording of high-quality signals at low energy (a nJ) pump pulses.
