Youlian Wang, Changping Xu, Rui Yang, Yinping Miao, Xiaolan Li, Jianquan Yao. "<i>In situ</i> detection of sodium nitrate and sodium nitrite using a cascade Fabry–Perot interferometer based on the photothermal effect." Applied Physics Letters (2025). https://doi.org/10.1063/5.0285021