Efficient, broadly-tunable source of megawatt pulses for multiphoton microscopy based on self-phase modulation in argon-filled hollow-core fiber

作     者：Eisenberg, Yishai Wang, Wenchao Zhao, Shitong Hebert, Eric S. Chen, Yi-Hao Ouzounov, Dimitre G. Takahashi, Hazuki Gruzdeva, Anna Laviolette, Aaron K. Labaz, Moshe Sidorenko, Pavel Antonio-Lopez, Enrique Amezcua-Correa, Rodrigo Yapici, Nilay Xu, Chris Wise, Frank 

作者机构：School of Applied and Engineering Physics Cornell University IthacaNY14853 United States Department of Neurobiology and Behavior Cornell University IthacaNY14853 United States Department of Physics Solid-State Institute Technion Israel Institute of Technology Haifa32000 Israel Department of Electrical and Computer Engineering Solid-State Institute Technion Israel Institute of Technology Haifa32000 Israel CREOL The College of Optics and Photonics University of Central Florida OrlandoFL32816 United States 

出 版 物：《arXiv》 (arXiv)

年 卷 期：2024年

核心收录：

主　　题：Fluorescence microscopy 

摘      要：An exciting recent development for deep-tissue imaging with cellular resolution is three-photon fluorescence microscopy (3PM) with excitation at long wavelengths (1300 and 1700 nm). In the last few years, long-wavelength 3PM has driven rapid progress in deep-tissue imaging beyond the depth limit of two-photon microscopy, with impacts in neuroscience, immunology, and cancer biology. However, wide adoption of 3PM faces challenges. Three-photon excitation (3PE) is naturally weaker than two-photon excitation, which places a premium on ultrashort pulses with high peak power. The inefficiency, complexity, and cost of current sources of these pulses present major barriers to the use of 3PM in typical biomedical research labs. Here, we describe a fiber-based source of femtosecond pulses with multi-megawatt peak power, tunable from 850 nm to 1700 nm. Compressed pulses from a fiber amplifier at 1030 nm are launched into an antiresonant hollow-core fiber filled with argon. By varying only the gas pressure, pulses with hundreds of nanojoules of energy and sub-100 fs duration are obtained at wavelengths between 850 and 1700 nm. This approach is a new route to an efficient, robust, and potentially low-cost source for multiphoton deep-tissue imaging. In particular, 960-nJ and 50-fs pulses are generated at 1300 nm with a conversion efficiency of 10%. The nearly 20-MW peak power is an order of magnitude higher than the previous best from femtosecond fiber source at 1300 nm. As an example of the capabilities of the source, these pulses are used to image structure and neuronal activity in mouse brain as deep as 1.1 mm below the dura. © 2024, CC BY.