Gas-filled Hollow-core Fiber Lasers and Advanced Optoelectronic Neural Interfaces for the Brain (Invited)

This work presents our recent research on the development of high pulse energy and narrow linewidth fiber lasers spanning from the near-infrared to the mid-infrared spectral domains, based on different antiresonant hollow-core fibers filled with active gases. We then discuss how the obtained lasers are used for photoacoustic gas sensing and bioimaging, such as real-time detection of CO2 with sub-ppm concentration and brain imaging. In the second part of this invited paper, we briefly present the development of novel multi-functional optoelectronic fibers with integrated metallic electrodes and microfluidic channels for electrophysiology and drug delivery in the brain, respectively with chronic and acute in vivo results.