Precise Frequency Measurement of the 2${}^1$S${}_0$-3${}^1$D${}_2$ Two-Photon Transition in atomic ${}^4$He

Yi-Jan Huang, Yu-Chan Guan, Yao-Chin Huang +4

We present the first precise frequency measurement of the 2${}^1$S${}_0$-3${}^1$D${}_2$ two-photon transition in ${}^4$He at 1009 nm. The laser source at 1009 nm is stabilized on a…