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Ground Band and a Generalized GP-equation for Spinor Bose-Einstein Condensates

C. G. Bao·Z. B. Li
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Abstract

For the spinor Bose-Einstein condensates both the total spin $S$ and its Z-component $S_{Z}$ should be conserved. However, in existing theories, only the conservation of $S_{z}$ has been taken into account. To remedy, this paper is the first attempt to take the conservation of both $% S$ and $S_{Z}$ into account. For this purpose, a total spin-state with the good quantum numbers $S$ and $S_{Z}$ is introduced in the trial wave function, thereby a generalized Gross-Pitaevskii equation has been derived. With this new equation, the ground bands of the $^{23}$Na and $% ^{87}$Rb condensates have been studied, where the levels distinct in $S$ split. It was found that the level density is extremely dense in the bottom of the ground band of $^{23}$Na, i.e., in the vicinity of the ground state. On the contrary, for $^{87}$Rb, the levels are extremely dense in the top of the ground band,

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C. G. Bao, Z. B. Li. 2004-09-08. Ground Band and a Generalized GP-equation for Spinor Bose-Einstein Condensates. https://doi.org/10.1103/physreva.70.043620

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