Compact optical fiber photoacoustic gas sensor with integrated multi-pass cell.

"data availability data will be made available on request. acknowledgements this work was supported by (62275106 62135006 62075170); (201904020032); (2019bt02x105); (2022a1515010105 2023a1515011415); (jcyj20220530153004009"

"Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper."

"This work was supported by 10.13039/501100001809National Natural Science Foundation of China (62275106, 62135006, 62075170); Guangzhou Science and Technology Plan Project (201904020032); Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program (2019BT02X105); 10.13039/501100003453Natural Science Foundation of Guangdong Province (2022A1515010105, 2023A1515011415); Science and Technology Innovation Commission of Shenzhen (JCYJ20220530153004009); Guangzhou Fundamental and Applied Fundamental Research Project (202201010578)."