RUI: Rapid and high-resolution hyperspectral imaging using frequency combs

Santa Clara University, Santa Clara CA

Investigators

Abstract

Real-time hyperspectral imaging is a powerful method for obtaining an image of an object by recording the way in which light of practically all colors interacts with the object in a point-by-point fashion. However, existing technologies have significant limitations, particularly in how well they can differentiate between the signals of target species and those of the background. With support from the Chemical Measurement and Imaging Program in the Division of Chemistry, Professor Lomsadze and his research group at Santa Clara University are developing and experimentally demonstrating a revolutionary approach to high-speed hyperspectral imaging. This novel method is predicted to provide capabilities that other methods cannot, including being able to "see" the signal of an item of interest against a bright and dynamic background. This is a valuable capability, as it has the potential to afford highly precise visualization of certain tiny items in a sea of others, such as when examining biological tissue, detecting individual particles of toxic materials in mixtures, identifying bacteria or diseased cells in specimens, and examining the surface of the Earth. This newly developed method will enable field-deployable devices for the broad spectrum of applications described above. This research project involves mentoring undergraduate students and educating them on a wide range of cutting-edge optical imaging and detection methods through their hands-on involvement in the design, construction, and use of a laser-based hyperspectral imaging system. These experiences prepare the undergraduate team well for opportunities in graduate school and/or research careers in high-technology industries, such as those in the local Silicon Valley region or elsewhere. The research further enhances Santa Clara University's scientific community and provide excellent directions for meaningful local outreach activities emphasizing cutting-edge, modern technologies for important new signal detection applications. Rapid and high-resolution hyperspectral imaging is an extremely powerful optical method that is used in fundamental science for studying optical properties of materials at the single-particle level. The imaging methods are also widely used outside the research laboratory for practical applications. However, many of these existing imaging methods face challenges in differentiating between signals from the target species and the cluttered background. In addition, the identification process becomes even more complex and near impossible when transitions are inhomogenously broadened and the transitions from different species overlap. Professor Lomsadze and his group at Santa Clara University are developing a novel imaging method that addresses these challenges by use of a method he coinvented, called tri-comb spectroscopy (TCS), a revolutionary approach to laser spectroscopy. TCS is a rapid, high-resolution and background-free optical method that enables the measurement of homogenous linewidth in inhomogenously broadened systems. It also provides information about whether the measured transitions belong to the same or different analytes in a mixture. The development of TCS-based microscopy imaging has a tremendous impact on fundamental chemistry and physics, as it will enable precision measurements of optical properties of materials. Furthermore, it provides a compact and powerful tool for studying the fast dynamics and localization effects of individual quantum systems (molecules, quantum dots and color centers) that are promising candidates for quantum computing. In the long term, this imaging method shows potential for application in tip-enhanced spectroscopy, which is anticipated to enable rapid, high-spectral, and sub-wavelength spatial resolution measurements of single objects, such as nanoparticles. Professor Lomsadze plans for integrating student research, education, and outreach activities, which exposes students, including those from underrepresented groups, to opportunities in the development of sophisticated instruments that address important measurement challenges. The research project also provides the students an experience enriched by participation in outreach activities with companies in Silicon Valley and exploration of future career opportunities. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.