Improvement of conversion efficiency of atom-molecule Bose-Einstein condensate

We investigate the stimulated Raman adiabatic passage in two-color photoassociation for a atom-molecule Bose-Einstein condensate. By applying two time-varying Guassian laser pulses that fulfill generalized two-photon resonance condition, we obtain highly efficient atom-molecule conversion. The efficiency depends on the free-bound detuning and the delay time between the two pulses. By adjusting the parameters optimally, we achieve 92% conversion efficiency.Comment: 4 pages, 4 figures. To be appeared in J. Korean Phys. Society (JKPS

Storage of spin squeezing in a two-component Bose-Einstein condensate

Efficient control of spin squeezing in a two-component Bose-Einstein Condensate is studied by rapidly turning-off the external field at a time that maximal spin squeezing appears. We show that strong reduction of spin fluctuation can be maintained in a nearly fixed direction for a long time. We explain the underlying physics unambiguously, and present analytical expressions of the maximal-squeezing time.Comment: 10 pages, 5 figures. This version is slightly different from the one published in Phys. Rev. Let

Spin squeezing and maximal-squeezing time

Spin squeezing of a nonlinear interaction model with Josephson-like coupling is studied to obtain time scale of maximal squeezing. Based upon two exactly solvable cases for two and three particles, we find that the maximal-squeezing time depends on the level spacing between the ground state and its next neighbor eigenstate.Comment: 7 pages, 5 figures, 1 table. Resubmitted to Phys. Rev.

On the Divisibility of Trinomials by Maximum Weight Polynomials over F2

Divisibility of trinomials by given polynomials over finite fields has been studied and used to construct orthogonal arrays in recent literature. Dewar et al.\ (Des.\ Codes Cryptogr.\ 45:1-17, 2007) studied the division of trinomials by a given pentanomial over \F_2 to obtain the orthogonal arrays of strength at least 3, and finalized their paper with some open questions. One of these questions is concerned with generalizations to the polynomials with more than five terms. In this paper, we consider the divisibility of trinomials by a given maximum weight polynomial over \F_2 and apply the result to the construction of the orthogonal arrays of strength at least 3.Comment: 10 pages, 1 figur