Krämer M, Pitaevskii L, Stringari S
Dipartimento di Fisica, Università di Trento, Istituto Nazionale per la Fisica della Materia, I-38050 Povo, Italy.
Phys Rev Lett. 2002 May 6;88(18):180404. doi: 10.1103/PhysRevLett.88.180404. Epub 2002 Apr 22.
The hydrodynamic equations of superfluids for a weakly interacting Bose gas are generalized to include the effects of periodic optical potentials produced by stationary laser beams. The new equations are characterized by a renormalized interaction coupling constant and by an effective mass accounting for the inertia of the system along the laser direction. For large laser intensities the effective mass is directly related to the tunneling rate between two consecutive wells. The predictions for the frequencies of the collective modes of a condensate confined by a magnetic harmonic trap are discussed for both 1D and 2D optical lattices and compared with recent experimental data.
弱相互作用玻色气体超流体的流体动力学方程被推广，以纳入由固定激光束产生的周期性光学势的影响。新方程的特征在于重整化的相互作用耦合常数以及考虑系统沿激光方向惯性的有效质量。对于大激光强度，有效质量与两个连续阱之间的隧穿率直接相关。针对一维和二维光学晶格，讨论了由磁谐波阱约束的凝聚体集体模式频率的预测，并与最近的实验数据进行了比较。
