High-power ultraviolet 278-nm laser from fourth-harmonic generation of an Nd:YAG amplifier in CsB<sub>3</sub>O<sub>5</sub> crystal

High-power ultraviolet 278-nm laser from fourth-harmonic generation of an Nd:YAG amplifier in CsB₃O₅ crystal

He Miao^{1, 2, 3}, Yang Feng^{1, 2, †}, Dong Cheng^{1, 2, 3}, Wang Zhi-Chao^{1, 2}, Yuan Lei^{1, 2}, Xu Yi-Ting^{1, ‡}, Zhang Guo-Chun², Wang Zhi-Min^{1, 2}, Bo Yong^{1, 2}, Peng Qin-Jun^{1, 2}, Cui Da-Fu¹, Wu Yi-Cheng², Xu Zu-Yan^{1, 2}

(color online) Experimental setup of the UV 278 nm laser. F1–F9: convergent lenses; TFP1, TFP2: thin film polarizers; AH1–AH6: diode-side-pumped Nd:YAG amplifier heads; QR1–QR3: 90° quarter rotators; QWP: quarter-wave plate; M1–M8: flat mirrors; HWP: half-wave plate; D1–D2: dump.