Entangled Photon Imaging and Microscopy for Chemical and Biological Investigations

Regents Of The University Of Michigan - Ann Arbor, Ann Arbor MI

Investigators

Abstract

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.