论文标题
Floquet Engineering拓扑狄拉克乐队
Floquet engineering topological Dirac bands
论文作者
论文摘要
我们在实验上实现了一个时间周期调制的1D晶格，用于具有一对线性频段的超电原子，每个晶体都与浮子绕组数：拓扑不变。这些乐队是旋转摩托车锁定的，几乎完美地在布里渊区（BZ）到处都是线性的，这使该系统近乎理想地实现了1d Dirac Hamiltonian。我们使用量子状态断层扫描形式表征了浮子绕组编号，覆盖了BZ并在一个浮雕时期进行微动作。最后，我们更改了调制时机以提高拓扑保护，从而在狄拉克点上张开缝隙，该差距与偏离拓扑配置的偏差成比例。
We experimentally realized a time-periodically modulated 1D lattice for ultracold atoms featuring a pair of linear bands, each associated with a Floquet winding number: a topological invariant. These bands are spin-momentum locked and almost perfectly linear everywhere in the Brillouin zone (BZ), making this system a near-ideal realization of the 1D Dirac Hamiltonian. We characterized the Floquet winding number using a form of quantum state tomography, covering the BZ and following the micromotion through one Floquet period. Lastly, we altered the modulation timing to lift the topological protection, opening a gap at the Dirac point that grew in proportion to the deviation from the topological configuration.
