Liyun Jiang

EIT-assisted large cross-Kerr nonlinearity in a four-level inverted-Y atomic system

A four-level inverted-Y scheme with an electromagnetically induced transparency (EIT) core is investigated for the enhancement of cross-Kerr effect in rubidium atoms. When detunings of the coupling and control fields are appropriately set, an enhanced EIT window is observed, and the induced phase shift of the probe field due to cross-phase modulation (XPM) is obtained by measuring the dispersive property of the probe transition. The maximal XPM phase shift is about 12° under the current experimental conditions. The experimental measurements agree well with the theoretical calculations. The enhanced XPM phase shift in such an atomic system has applications in quantum nonlinear optics and quantum information science.

TR-LIF LIFETIME MEASUREMENTS AND HFR+CPOL CALCULATIONS OF RADIATIVE PARAMETERS IN VANADIUM ATOM (V I)

Radiative lifetimes of 79 levels belonging to the 3d {sup 3}4s4p, 3d {sup 4}4p, 3d {sup 3}4s5p, 3d {sup 4}5p, and 3d {sup 3}4s4d configurations of V I with energy from 26,604.807 to 46,862.786 cm{sup –1} have been measured using time-resolved laser-induced fluorescence (TR-LIF) spectroscopy in laser-produced plasma. The lifetime values reported in this paper are in the range of 3.3-494 ns, and the uncertainties of these measurements are within ±10%. A good agreement was obtained with previous data. HFR+CPOL calculations have been performed and used to combine the calculated branching fractions with the available experimental lifetimes to determine semi-empirical transition probabilities for 784 V I transitions.

Radiative lifetime measurements of some Gd I and Gd II levels using time-resolved laser spectroscopy

Radiative lifetimes of 27 levels (27?041.751?38?434.97?cm?1) in Gd I and 27 levels (27?130.397?45?394.925?cm?1) in Gd II have been measured using the time-resolved laser-induced fluorescence method. Laser ablation was used to generate Gd atoms and ions on a Gd plate. The measured lifetime values range from 4.0 to 90?ns with an uncertainty of 5% or less. Of all the results, to our knowledge, lifetimes of 23 Gd II levels and 11 Gd I levels are reported for the first time. Good agreement between our results and the previous ones has been achieved.

Experimental branching fractions, transition probabilities and oscillator strengths in Gd I and Gd II

Branching fractions of 13 levels in Gd I and 12 levels in Gd II were experimentally determined based on the emission spectrum of a hollow cathode lamp. In addition, transition probabilities and oscillator strengths for 66 lines of Gd I and 74 lines of Gd II were derived from a combination of the radiative lifetimes reported in the earlier literature and the branching fractions obtained in the present paper.

Experimental branching fractions, transition probabilities, and oscillator strengths in Sn I

Branching fractions of Sn I for 66 spectral lines from the even-parity 5pnp (n=7, 8, 11–13, 17–19, 27, 32) and 5pnf (n=4–7, 9, 11, 13, 16, 18) levels and the odd-parity 5p6s level have been experimentally determined based on the emission spectrum of a hollow cathode lamp. In addition, transition probabilities and oscillator strengths for 59 lines among the above ones have been derived from a combination of the radiative lifetimes reported in the literature and the branching fractions obtained in the present paper.