大散射长度的光晶格：用少体物理模拟电子-声子系统
Optical lattices with large scattering length: Using few-body physics to simulate an electron-phonon system
摘要：
我们建议超越通常的哈伯德模型描述的原子在光晶格，并显示如何少体物理可以用来模拟多体现象，例如，电子-声子系统我们把一个原子物种被困在一个深的光晶格在完全填充和另一个未被捕获的自旋极化费米子（看不到光晶格），但有一个s波接触相互作用的第一个物种。对于晶格间距量级的大的正散射长度，通常的两体束缚态（二聚体）重叠形成在整个晶格上延伸的巨轨道，其可以被视为未被捕获的物质的“电子”带，而被捕获的原子成为具有其自身的现场动力学的“离子”，从而模拟具有声子频率和Peierls跃迁的重整化的电子-声子系统。这种设置需要大的散射长度，但最大限度地减少损失，不需要更高的频带，并增加了新的自由度，这不能很容易地描述在晶格变量，从而开辟了有趣的可能性，探索有趣的物理在少体和多体系统之间的接口。
英文摘要：
We propose to go beyond the usual Hubbard model description of atoms in optical lattices and show how few-body physics can be used to simulate many-body phenomena, e.g., an electron-phonon system. We take one atomic species to be trapped in a deep optical lattice at full filling and another to be untrapped spin-polarized fermions (which do not see the optical lattice) but has an s-wave contact interaction with the first species. For large positive scattering length on the order of lattice spacing, the usual two-body bound (dimer) states overlap forming giant orbitals extending over the entire lattice, which can be viewed as an "electronic" band for the untrapped species while the trapped atoms become the "ions" with their own on-site dynamics, thereby simulating an electron-phonon system with renormalization of the phonon frequencies and Peierls transitions. This setup requires large scattering lengths but minimises losses, does not need higher bands and adds new degrees of freedom which cannot easily be described in terms of lattice variables, thus opening up intriguing possibilities to explore interesting physics at the interface between few-body and many-body systems.
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。
