Domain-wall dynamics in Bose–Einstein condensates with synthetic gauge fields
Domain-wall dynamics in Bose–Einstein condensates with synthetic gauge fields
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DOI：
10.1038/s41586-021-04250-3
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发表时间：
2021-05
期刊：
影响因子：
64.8
通讯作者：
Kai-Xuan Yao;Zhendong Zhang;C. Chin
中科院分区：
文献类型：
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作者：
Kai-Xuan Yao;Zhendong Zhang;C. Chin
从凝聚态物质到高能物理，多体物理系统中的相互作用导致了奇异粒子的出现。例子是量子色动力学中的介子和分数量子霍尔系统中的复合费米子，它们是由物质和规范场之间的动态耦合产生的。量子模拟可以帮助理解物质与规范相互作用的复杂性，超冷原子通过创建人工规范场提供了一个多功能平台。模拟奇异涌现粒子物理的一个重要步骤是人工规范场的合成，其状态动态取决于物质的存在。在这里，我们展示了稳定的玻色-爱因斯坦凝聚体中畴壁的确定性形成，其规范场由原子密度决定。密度相关的规范场是通过光学晶格势和原子间相互作用的同时调制而产生的，并导致原子域凝聚成两个不同的动量。将畴壁建模为基本激发，我们发现畴壁响应合成电场的荷质比大于裸原子的荷质比且与裸原子的荷质比相反。我们的工作为模拟具有动态规范场的量子系统中先前未描述的激发的动力学和相互作用提供了广阔的前景。
Interactions in many-body physical systems, from condensed matter to high-energy physics, lead to the emergence of exotic particles. Examples are mesons in quantum chromodynamics and composite fermions in fractional quantum Hall systems, which arise from the dynamical coupling between matter and gauge fields,. The challenge of understanding the complexity of matter–gauge interaction can be aided by quantum simulations, for which ultracold atoms offer a versatile platform via the creation of artificial gauge fields. An important step towards simulating the physics of exotic emergent particles is the synthesis of artificial gauge fields whose state depends dynamically on the presence of matter. Here we demonstrate deterministic formation of domain walls in a stable Bose–Einstein condensate with a gauge field that is determined by the atomic density. The density-dependent gauge field is created by simultaneous modulations of an optical lattice potential and interatomic interactions, and results in domains of atoms condensed into two different momenta. Modelling the domain walls as elementary excitations, we find that the domain walls respond to synthetic electric field with a charge-to-mass ratio larger than and opposite to that of the bare atoms. Our work offers promising prospects to simulate the dynamics and interactions of previously undescribed excitations in quantum systems with dynamical gauge fields.