弛豫与关联效应对NII离子2s~22p3s~3P_1—2s~22p~2~1D_2与2s~22p3s~1P_1—2s~22p~2~3P_(0,1,2)自旋禁戒跃迁概率的影响

G. Z. Zhang, M. Katsuragawa, K. Hakuta +2 more

The sum-frequency generation process using strong-field coupling and quantum interference is described systematically using atomic hydrogen both in theory and experiment. It is shown that strong coupling at the 3p-2s transition creates destructive interference to reduce the linear susceptibility at the resonant 3p\ensuremath{\leftarrow}1s transition. Simultaneously, two-photon coupling of the 2s and 1s states produces constructive interference to resonantly enhance the nonlinear susceptibility for sum-frequency generation at the 3p\ensuremath{\rightarrow}1s (Lyman-\ensuremath{\beta}) transition. Experimental results clearly demonstrate the theoretical predictions. When the Rabi frequency for the 3p-2s coupling exceeds the Doppler tail of the medium, the photoion signals on resonance are suppressed significantly because of induced transparency. The generated Lyman-\ensuremath{\beta} radiation grows rapidly by a factor of 250 at an atom density of ${10}^{15}$ ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}3}$ and interaction length of 3.5 cm, resulting in a conversion efficiency of 2\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}4}$.

杨保东 Yang Baodong, 赵江艳, 梁强兵 +3 more

白光, 晴天

J. J. Wright, L. C. Balling

Cross sections for 1P1→3P1 excitation transfer in Ca and Sr have been measured for the noble gases, using simultaneous measurements of the integrated 1P1 and 3P1 fluorescence intensities and the observed 1P1 decay rate. The cross sections range from 10−18 to 10−16 cm2.

E. V. Baklanov, Sergey M Kobtsev, А. В. Тайченачев

We demonstrate the possibility of measuring the forbidden 1S-2S transition frequency (121 nm) of hydrogen atom by the method of stimulated Raman scattering (SRS) when atom from the 1S level moves to the 2S level through the intermediate 3P level. The frequency of the pumping field (103 nm) is close to the frequency of transition 3P-1S, and the frequency of the stimulated scattering (656 nm) - to the frequency of transition 3P-2S.

刘全慧, 王鑫