Flexible beam delivery of ultrafast laser through vacuum-pumped anti-resonant hollow-core fiber

• Published in: Frontiers in physics Vol. 11
• Main Authors: Cai, Yiming, Mai, Yifan, Xiang, Shen, Shi, Jianhong, Zhu, Qixin, Li, Rong, Li, Jinyan, Li, Cheng, Yan, Dapeng, Xing, Yingbin
• Format: Journal Article
• Language: English
• Published: Frontiers Media S.A 02-03-2023
• Subjects: anti-resonant fiber; AR-HCF; flexible beam delivery; ultrafast laser delivery; vacuum-pumped HCF
• ISSN: 2296-424X; 2296-424X
• DOI: 10.3389/fphy.2023.1160287

We demonstrate the transmission of a 100 MW-peak-power ultrafast laser through a 5-m anti-resonant hollow-core fiber (AR-HCF) with a pumpable armored tube for air exhaust. The AR-HCF consists of a 45-μm-hollow-core and seven untouched capillaries with an attenuation of 0.11 dB/m measured at a wavelength of 1030 nm. We investigate the effect of air-filling and vacuum pumping on transmission efficiency and pulse distortion. The comparison reveals the importance of controlling air concentration in hollow-core fibers (HCFs) for achieving high transmission efficiency and pulse quality. With the suppression of air concentration, the transmission efficiency increases from 61% to 72%, and pulse distortion is effectively controlled. The results demonstrate the potential of AR-HCFs for high-power ultrafast laser delivery systems for various applications. The pumpable armored tube design provides a simple and effective solution to suppress self-phase modulation (SPM) and enable flexible beam delivery.