Oscillator strengths for spin-changing S - P transitions in He

Margaret N. Lewis, Louis C. Green

D. C. Morton, Eva Schulhoff, G. W. F. Drake

Abstract We have calculated the electric dipole (E1) and magnetic quadrupole (M2) oscillator strengths and spontaneous decay rates for 24 spin-changing transitions of atomic helium. We included the effects of the finite nuclear mass and the anomalous magnetic moment of the electron augmented by the recently derived Pachucki term. The specific transitions for 4 He are and with and for For the E1 calculations we used the Breit approximation and pseudostate expansions to perform the perturbation sums over intermediate states in both the length and velocity gauge as a check on both numerical accuracy and validity of the transition operators. The corrections for the nuclear mass and the electron anomaly tend to cancel, indicating that if one is included, then so should be the other. The tables give mass- and anomaly-dependent coefficients permitting the easy generation of results for the other isotopes of helium.

C. Lhuillier, Franck Laloë

Shaobing Zhu, Jun Qian Jun Qian, Yuzhu Wang Yuzhu Wang

We investigate the spin dynamics, starting from the initial band-insulating state, of fermionic high-spin atoms in optical superlattices. Through numerical simulations and analytical calculations, we determine the time evolution behavior of the system. When the spin-changing strength and tunneling strength are comparable, the spin dynamics feature a spin-changing oscillation with the amplitude modulated by the superexchange interaction. When the double-well potential is very shallow, the spin dynamics feature a simple harmonic oscillation with the oscillation frequencies related only to the spin-changing strength, which can be properly explained with the perturbation model.

Decheng Ma, Chenglong Jia

We theoretically investigate the dynamics of polar bright soliton under the influence of spin-orbit coupling (SOC) in spin-1 three component Bose-Einstein condensate (BEC). Periodically oscillating dark-bright-dark solitons are found to be induced by the SOC with their multifrequency oscillations jointly determined by the interparticle nonlinear interaction and the SOC strength. Explicit formulas are provided to identify these frequencies, which are in good agreement with the numerical simulation results. A linear Zeeman interaction is further introduced to break the time-reversal symmetry and change the polarity of the spinor BECs, which results in the periodic transition of the system from polar state to ferromagnetic state.

Vladimir V. Dmitriev