双阱光晶格中的冷原子
Cold atoms in double-well optical lattices
摘要：
研究了双阱光晶格中的冷原子。导出了有效哈密顿量的赝自旋表示。处于平衡状态的系统表现为有序和无序两个阶段。相之间的二级相变可以由温度或通过改变系统参数来驱动。集体赝自旋激发在相变点处有一个消失的能隙。研究了原子以初始非平衡态加载到晶格中时的动力学。结果表明，原子的时间演化，相反，他们的平衡热力学，不能在平均场近似描述，因为它会导致在结构上不稳定的动力学系统，但更准确的描述是必要的考虑衰减效应。
英文摘要：
Cold atoms, loaded into an optical lattice with double-well sites, are considered. Pseudospin representation for an effective Hamiltonian is derived. The system in equilibrium displays two phases, ordered and disordered. The second-order phase transition between the phases can be driven either by temperature or by changing the system parameters. Collective pseudospin excitations have a gap disappearing at the phase-transition point. Dynamics of atoms is studied, when they are loaded into the lattice in an initially nonequilibrium state. It is shown that the temporal evolution of atoms, contrary to their equilibrium thermodynamics, cannot be described in the mean-field approximation, since it results in a structurally unstable dynamical system, but a more accurate description is necessary taking account of attenuation effects.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
