Entangled Photon Imaging and Microscopy for Chemical and Biological Investigations

在化学系化学测量和成像项目和理解大脑计划的支持下，密歇根大学的古德森教授和他的团队正在开发一种光学技术，以提高成像空间分辨率，同时对样品的损害最小。光学显微镜的使用在过去十年中取得了巨大进步。许多光学显微方法已用于材料和生物成像以及化学传感。虽然这些技术在灵敏度方面具有很大的前景，但有些技术确实需要高且可能具有破坏性的照明光强度。现在需要的是一种化学成像技术，该技术利用两个光子过程的高度聚焦行为，但同时将峰值强度保持在较低水平。古德森教授正在开发的成像技术使用光子对的量子态相互连接的光束，即纠缠光子。古德森教授和他的团队利用量子纠缠的特性，用极少量的光子以极高的分辨率探测和成像分子。 随后开发的技术使他们能够研究有趣的生物系统，例如组织成像和阿尔茨海默病患者淀粉样蛋白的形成。 美国国家科学基金会的支持还有助于在化学、物理和材料科学等领域培训和指导多元化的科学家（研究生和博士后）。利用这笔资助，密歇根大学的古德森教授和他的研究小组正在研究一种通过纠缠双光子吸收（ETPA）显微镜实现化学敏感性的新方法。纠缠双光子显微镜概念提供了对经典 TPA 显微镜的突破，允许激发强度降低 10 个数量级，这对于生物和材料应用非常重要。该项目的目标是 a) 证明 ETPA 显微镜在极低输入通量下的灵敏度极限，b) 测试 ETPA 显微镜在极低输入通量和增强的空间分辨率下探测重要化学过程的能力，以及 c) 将该方法应用于重要的化学系统，说明 ETPA 显微镜方法的影响。这项工作的更广泛影响：a) 通过 WISE 项目为中学生提供光学方面的暑期教育经验，b) 为高中生提供更广泛的化学和物理经验，重点是光学，以及 c) 为可能对包括光学在内的物理科学有浓厚兴趣的下一代教授开发和扩大研讨会。 这项研究的影响还包括为化学和成像界提供一种新方法，其中包含有关方法、材料和理论细节的重要细节。

With support from the Chemical Measurement and Imaging Program in the Division of Chemistry and the Understanding the Brain Initiative, Professor Goodson at the University of Michigan and his group are developing an optical technique to enhance imaging spatial resolution with minimal damage to samples. The use of optical microscopy has greatly progressed over the last decade. Many optical microscopic methods have been used in materials and biological imaging as well as chemical sensing. While these techniques hold great promise in sensitivity, some do require high and potentially damaging light intensities in illumination. What is now needed, is a chemical imaging technique which takes advantage of the highly focused behavior of the two photon process, but at the same time it keeps the peak intensity at low levels. The imaging technique under development by Professor Goodson uses a beam of light where the quantum states of photon pairs are linked, i.e. entangled photons. Utilizing the property of quantum entanglement, Professor Goodson and his group probe and image molecules with extremely high resolution and with a very small number of photons. The developed technique subsequently enables them to study interesting biological systems such as tissue imaging and the formation of amyloids with Alzheimer's patients. This support from the National Science Foundation also helps to train and mentor a diverse group of scientists (graduate students and postdoctoral students) in areas such as chemistry, physics and materials science.With this grant, Professor Goodson at the University of Michigan and his research group are investigating a new approach to chemical sensitivity through entangled two-photon absorption (ETPA) microscopy. The entangled two-photon microscopy concept provides a breakthrough over the classical TPA microscopy allowing 10 orders of magnitude lower excitation intensity which is of immense importance for biological and materials applications. The objectives of the project are to a) demonstrate the limits of sensitivity of the ETPA microscopy at very low input flux, b) test the ETPA microscope's ability to probe important chemical processes at very low input flux and with enhanced spatial resolution, and c) apply the methodology to an important chemical system illustrating the impact of the ETPA microscopy method. The broader impact of the work: a) provides summer educational experience in optics through the WISE program for middle school students, b) provides a broader experience for high school students in chemistry and physics with an emphasis on optics, and c) develops and expands a workshop for the next generation professors who might have a strong interest in the physical sciences including optics. The impact of this investigation also includes providing the chemical and imaging community a new approach with important details regarding the specifics of the methodology, materials, and theory.