Development of an Ultrasensitive Ultrafast Phase Spectrometer

超灵敏超快相位光谱仪的研制

• 批准号: 0116564
• 负责人: Rick Trebino
• 金额: $ 70万
• 依托单位: Georgia Tech Research Corporation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-09-01 至 2005-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0116564&HistoricalAwards=false
• 关键词: Development; Ultrasensitive; Ultrafast; Phase; Spectrometer

A grant has been awarded to Drs Trebino and El-Sayed at the Georgia Institute of Technol-ogy to develop a novel ultrasensitive ultrafast intensity-and-phase spectrometer, which yields the full intensity and phase vs. time (or frequency) of luminescence and other light pulses relevant to biology and many other fields. The spectrometer will have a very high sensitivity for single-shot measurements and a 1-photon-per-pulse sensitivity for multi-shot measurements. These sensitivi-ties are approximately six orders magnitude better than those of current measurement techniques.The proposed instrument involves combining a spectrometer with a coherent reference light pulse. Specifically, it will use an ultra-short pulse with a spectrum ranging from 400 nm to 1600 nm and generated by propagating readily available, low-energy, 100-fs pulses through microstruc-ture optical fiber (recently developed by Lucent Technologies. Demonstrations of the new instru-ment will involve simple photochemical systems relevant to photobiology. Examples include dou-ble proton transfer processes in 7-azaindole and its analogues (important in understanding radiation-induced DNA mutation) and the photo-isomeri-zation around double bonds, e.g., in the merocyanine dyes (important for understanding of the primary processes in proteins of vision, such as rhodopsin and bacteriorhodopsin photosynthesis). Later, we propose to use this device to further understand the complex primary dynamics in bacteriorhodopsin and to distinguish between different theoretical models proposed for its primary photo-dynamics.This instrument will also have applications far beyond biology. For example, semi-conductor experiments often generate weak light pulses of new wavelengths, which cannot be measured with conventional methods, but potentially can with this. Also, astronomers routinely measure the intensity vs. frequency (the spectrum) of light from astrophysical sources, but they cannot currently measure the spectral phase. With this instrument it should be possible to do so and yield information previously unavailable regarding extraterrestrial light sources. In addition, the spectrometer will allow measurements of the phase of signal and idler beams in a broadband optical parametric generators-a system that is interesting because the phase of these two beams is quan-tum-mechanically entangled with many degrees of freedom and so can be used for quantum com-puting. Finally, the ultrafast intensity and phase vs. time of virtually any light-emitting medium could be studied using this highly sensitive instrument.

格鲁吉亚理工学院的Trebino和El-Sayed博士获得了一笔赠款，用于开发一种新型的超灵敏超快强度和相位光谱仪，该光谱仪可以产生与生物学和许多其他领域相关的发光和其他光脉冲的全部强度和相位与时间（或频率）的关系。光谱仪将具有非常高的单次测量灵敏度和1光子/脉冲的多次测量灵敏度。 这些灵敏度比现有的测量技术高出约六个数量级。所提出的仪器包括光谱仪和相干参考光脉冲。 具体来说，它将使用光谱范围从400 nm到1600 nm的超短脉冲，并通过传播容易获得的低能量100 fs脉冲通过微结构光纤（最近由朗讯科技公司开发）产生。新仪器的演示将涉及与光生物学有关的简单光化学系统。 实例包括7-氮杂吲哚及其类似物中的双质子转移过程（在理解辐射诱导的DNA突变中很重要）和双键周围的光异构化，例如，在mercury染料（重要的是了解初级过程中的蛋白质的视觉，如视紫红质和细菌视紫红质光合作用）。 之后，我们建议使用该设备来进一步了解细菌视紫红质中复杂的初级动力学，并区分其初级光动力学的不同理论模型。该仪器还将具有远远超出生物学的应用。 例如，半导体实验通常会产生新波长的弱光脉冲，这无法用传统方法测量，但可能可以用这种方法测量。 此外，天文学家通常测量来自天体物理源的光的强度与频率（光谱），但他们目前无法测量光谱相位。 有了这一仪器，应该可以这样做，并产生以前无法获得的关于外星光源的信息。 此外，该光谱仪还可以测量宽带光参量发生器中信号光和闲频光的相位，这是一个有趣的系统，因为这两束光的相位是量子纠缠的，具有多个自由度，因此可以用于量子计算。 最后，几乎任何发光介质的超快强度和相位与时间的关系都可以使用这种高灵敏度的仪器进行研究。