Label-Free Multicellular Imaging by Engineering the Light

New generations of laser sources, with high pulse energy, wide continuous tunable range, and a compact form, are in high demand to advance two-photon and three-photon microscopy to its full potential for deep-tissue imaging. Multimode fibers (MMFs) have emerged as an early but promising candidate. Effective control of nonlinear processes at high power levels in MMFs would unlock new possibilities for diverse applications including high-power fiber lasers, which potentially addresses the aforementioned need.

This talk discusses a recently developed approach that exploits the spatial and temporal degrees of control of nonlinear effects in step-index MMFs using a 3D-printed programmable fiber shaper. By leveraging the rich spatiotemporal degrees of freedom and the high spectral brilliance in SI MMF, You's team has achieved the broadband high-peak power spanning 560-2200 nm, resulting from combined spectral energy reallocation, up to 166-fold, and temporal shortening, up to 4-fold, uniquely enabled by the fiber shaper. Its potential as a nonlinear imaging source is further demonstrated by applying the MMF source to multiphoton microscopy, where multi-fold signal enhancement is achieved for label-free tissue imaging with adaptive optimization.

About the presenter
Sixian You, Ph.D., is an assistant professor in the Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, and the principal investigator of the Computational Biophotonics Laboratory at MIT Research Laboratory of Electronics. Her research focuses on developing biophotonics and microscopy solutions for better understanding and treatment of human diseases. You earned her master’s degree and doctorate in microscopy from University of Illinois at Urbana-Champaign and did her postdoctoral work on computational imaging at University of California at Berkeley.