SGER: Detection of Optical Absorption from Individual Molecules Using Sagnac Interferometry

SGER：使用萨格纳克干涉仪检测单个分子的光学吸收

• 批准号: 0241012
• 负责人: William Moerner
• 金额: $ 9.97万
• 依托单位: Stanford University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-03-15 至 2004-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0241012&HistoricalAwards=false
• 关键词: SGER; Detection; Optical; Absorption; Individual

Professors William E. Moerner and Martin M. Fejer of Stanford University are supported by the Analytical and Surface Chemistry and Atomic and Molecular Optics Programs to detect individual molecules using optical absorption and a Sagnac interferometer. The idea of this Small Grant for Exploratory Research is to avoid the dependence on fluorescence, which is the basis of most single molecule spectroscopy at present. Absorption would be a much more global approach, but is usually not as sensitive due to high background noise. Sagnac interferometry directly measures the difference in optical phase shift experienced by beams traveling clockwise versus counterclockwise in a ring. It is insensitive to excess phase amplitude and phase noise from the probing laser. Saturation modulation of the molecular absorption with a secondary pulsed laser will be used to make the molecular absorption time varying. By scanning the detection volume of the probe laser over the sample, microscopic images of ultrasmall features can be generated. The project has the potential to impact several fields including trace detection, biophysics, materials science, quantum information and nanoscience. In biological cells, for example, it would be possible to perform single molecule spectroscopy without dye labels, which potentially perturb the system, and without interference from spurious emitters.

威廉·E.作者声明：Martin M.斯坦福大学的费耶尔在分析和表面化学以及原子和分子光学计划的支持下，利用光学吸收和萨格纳克干涉仪检测单个分子。 这项探索性研究小额资助的想法是避免对荧光的依赖，这是目前大多数单分子光谱学的基础。 吸收将是一种更具全局性的方法，但由于背景噪音高，通常不那么敏感。 Sagnac干涉法直接测量在环中顺时针与逆时针行进的光束所经历的光学相移的差异。 它对来自探测激光的过量相位振幅和相位噪声不敏感。 利用二次脉冲激光对分子吸收进行饱和调制，使分子吸收随时间变化。 通过在样品上扫描探测激光器的检测体积，可以生成超小特征的显微图像。 该项目有可能影响多个领域，包括痕量检测、生物物理学、材料科学、量子信息和纳米科学。 例如，在生物细胞中，可以在没有染料标记的情况下进行单分子光谱分析，染料标记可能会干扰系统，并且没有杂散发射体的干扰。