Simulating and detecting artificial magnetic fields in trapped atoms

Simulating twistronics without a twist

Rotational misalignment or twisting of two mono-layers of graphene strongly influences its electronic properties. Structurally, twisting leads to large periodic supercell structures, which in turn can support intriguing strongly correlated behaviour. Here, we propose a highly tunable scheme to synthetically emulate twisted bilayer systems with ultracold atoms trapped in an optical lattice. In our scheme, neither a physical bilayer nor twist is directly realized. Instead, two synthetic layers are produced exploiting coherently-coupled internal atomic states, and a supercell structure is generat…

Simulating Z_2 topological insulators with cold atoms in a one-dimensional optical lattice

We propose an experimental scheme to simulate and detect the properties of time-reversal invariant topological insulators, using cold atoms trapped in one-dimensional bichromatic optical lattices. This system is described by a one-dimensional Aubry-Andre model with an additional SU(2) gauge structure, which captures the essential properties of a two-dimensional Z2 topological insulator. We demonstrate that topologically protected edge states, with opposite spin orientations, can be pumped across the lattice by sweeping a laser phase adiabatically. This process constitutes an elegant way to tra…

Simulating Chiral Magnetic and Separation Effects with Spin-Orbit Coupled Atomic Gases

The chiral magnetic and chiral separation effects---quantum-anomaly-induced electric current and chiral current along an external magnetic field in parity-odd quark-gluon plasma---have received intense studies in the community of heavy-ion collision physics. We show that analogous effects occur in rotating trapped Fermi gases with Weyl-Zeeman spin-orbit coupling where the rotation plays the role of an external magnetic field. These effects can induce a mass quadrupole in the atomic cloud along the rotation axis which may be tested in future experiments. Our results suggest that the spin-orbit …

Topological superfluid transition in bubble-trapped condensates

Ultracold quantum gases are highly controllable and, thus, capable of simulating difficult quantum many-body problems ranging from condensed matter physics to astrophysics. Although experimental realizations have so far been restricted to flat geometries, recently also curved quantum systems, with the prospect of exploring tunable geometries, are produced in microgravity facilities as ground-based experiments are technically limited. Here we analyze bubble-trapped condensates, in which the atoms are confined on the surface of a thin spherically-symmetric shell by means of external magnetic fie…

Anyon optics with time-of-flight two-particle interference of double-well-trapped interacting ultracold atoms

The subject of bianyon interference with ultracold atoms is introduced through theoretical investigations pertaining to the second-order momentum correlation maps of two anyons (built upon spinless and spin-1/2 bosonic, as well as spin-1/2 fermionic ultracold atoms) trapped in a double-well optical trap. The two-particle system is modeled according to the recently proposed protocols for emulating an anyonic Hubbard Hamiltonian in ultracold-atom one-dimensional lattices. Because the second-order momentum correlations are mirrored in the time-of-flight second-order interference patterns in space…

Synthetic superfluid chemistry with vortex-trapped quantum impurities

We explore the effect of using two-dimensional matter-wave vortices to confine an ensemble of bosonic quantum impurities. This is modelled theoretically using a mass-imbalanced homogeneous two component Gross-Pitaevskii equation where each component has independent atom numbers and equal atomic masses. By changing the mass imbalance of our system we find the shape of the vortices are deformed even at modest imbalances, leading to barrel shaped vortices; which we quantify using a multi-component variational approach. The energy of impurity carrying vortex pairs are computed, revealing a mass-de…

引力波与被俘获玻色-爱因斯坦凝聚体的相互作用

Interaction between gravitational waves and trapped Bose-Einstein condensates

本研究受利用BEC探测引力波的方案启发，探究引力波与被俘获玻色-爱因斯坦凝聚体的相互作用，分析引力波引发的多体态保真度振幅相移，以及各向异性简谐势约束下理想和有相互作用BEC的相移增强情况。

光学捕获人工极化激元分子中σ-π耦合与模式选择的观测

Observation of σ-πcoupling and mode selection in optically trapped artificial polariton molecules

本研究利用光学捕获的极化激元凝聚体，探索第一激发p态流形间的耦合，揭示基于激发参数的丰富图案，并展示其在模拟σ和π分子成键机制方面的潜力。

探测光学晶格中简并能带的拓扑不变量

Detecting degenerate bands topological invariants in optical lattice

本研究提出利用二维六角光学晶格中的超冷费米子，通过引入惯性力等实现非平凡拓扑的简并四能带模型，结合猝灭与飞行时间探测提取自旋陈数，验证拓扑不变量的鲁棒性。

利用自旋-轨道耦合的玻色-爱因斯坦凝聚体模拟谐振腔量子电动力学的再审视

Simulating cavity QED with spin-orbit coupled Bose-Einstein condensates revisited

本文研究自旋-轨道耦合玻色-爱因斯坦凝聚体在模拟谐振腔量子电动力学中的能力，发现其能再现单原子与量化场的相互作用，但无法捕捉集体效应如迪克模型中的多体纠缠。

Vortices in p-Wave Superfluids of Trapped Fermionic Atom Gases

In order to help detecting superfluidity, we theoretically investigate p-wave pairing superfluids in neutral Fermion atom gases confined by a three dimensimentional (3D) harmonic potential. The Ginzburg-Landau framework, which is generic for p-wave superfluids, is used to describe the order parameter spatial structure, or texture characterized by the l-vector both at rest and under rotation. The l-vector configuration is strongly contrained by the boundary condition due to a trap. It is found that the ground state textures exhibit spontaneous supercurrent at rest both cigar and pancake shape t…

Ultracold-atom quantum simulator for attosecond science

A quantum simulator based on ultracold optically trapped atoms for simulating the physics of atoms and molecules in ultrashort intense laser fields is introduced. The slowing down by about 13 orders of magnitude allows to watch in slow motion the tunneling and recollision processes that form the heart of attosecond science. The extreme flexibility of the simulator promises a deeper understanding of strong-field physics, especially for many-body systems beyond the reach of classical computers. The quantum simulator can experimentally straightforwardly be realized and is shown to recover the ion…