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arXiv · 2408.13789

Multi-watt long-wavelength infrared femtosecond lasers and resonant enamel ablation

Xuemei Yang·Dunxiang Zhang·Weizhe Wang·Kan Tian·Linzhen He·Jinmiao Guo·Bo Hu·Tao Pu·Wenlong Li·Shiran Sun·Chunmei Ding·Han Wu·Kenkai Li·Yujie Peng·Jianshu Li·Yuxin Leng·Houkun Liang
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Abstract

High-power broadband tunable long-wavelength infrared (LWIR) femtosecond lasers operating at fingerprint wavelengths of 7-14 {\mu}m hold significant promise across a range of applications, including molecular hyperspectral imaging, strong-field light-matter interaction, and resonant tissue ablation. Here we present 6-12 {\mu}m broadband tunable parametric amplifier based on LiGaS2 or BaGa4S7, generating new record output power of 2.4 W at 7.5 {\mu}m, and 1.5 W at 9.5 {\mu}m, pumped by a simple and effective thin-square-rod Yb:YAG amplifier producing 110 W 274 fs output pulses. As a proof of concept, we showcase efficient resonant ablation and microstructure fabrication on enamel at the hydroxyapatite resonant wavelength of 9.5 {\mu}m, with a laser intensity two orders-of-magnitude lower than that required by non-resonant femtosecond lasers, which could foster more precision surgical applications with superior biosafety.

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Xuemei Yang, Dunxiang Zhang, Weizhe Wang, Kan Tian, Linzhen He, Jinmiao Guo, Bo Hu, Tao Pu, Wenlong Li, Shiran Sun, Chunmei Ding, Han Wu, Kenkai Li, Yujie Peng, Jianshu Li, Yuxin Leng, Houkun Liang. 2024-08-25. Multi-watt long-wavelength infrared femtosecond lasers and resonant enamel ablation. https://arxiv.org/abs/2408.13789

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