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arXiv · 2210.01967

In vivo three- and four-photon fluorescence microscopy using a 1.8 $\mu$m femtosecond fiber laser system

Hideji Murakoshi·Hiromi H. Ueda·Ryuichiro Goto·Kosuke Hamada·Yutaro Nagasawa·Takao Fuji
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Abstract

Multiphoton microscopy has enabled us to image cellular dynamics in vivo. However, the excitation wavelength for imaging with commercially available lasers is mostly limited between 650-1040 nm. Here we develop a femtosecond fiber laser system that produces $\sim$150 fs pulses at 1.8 $\mu$m. Our system starts from an erbium-doped silica fiber laser, and its wavelength is converted to 1.8 $\mu$m using a Raman shift fiber. The 1.8 $\mu$m pulses are amplified with a two-stage Tm:ZBLAN fiber amplifier. The final pulse energy is $\sim$1 $\mu$J, sufficient for in vivo imaging.

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Hideji Murakoshi, Hiromi H. Ueda, Ryuichiro Goto, Kosuke Hamada, Yutaro Nagasawa, Takao Fuji. 2022-10-05. In vivo three- and four-photon fluorescence microscopy using a 1.8 $\mu$m femtosecond fiber laser system. https://arxiv.org/abs/2210.01967

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