标题： 相干性的出现和量子相变的动力学 显示英文标题

标题： Emergence of coherence and the dynamics of quantum phase transitions

摘要： 量子相变的动力学是现代多体物理中最具挑战性的问题之一。 在这里，我们通过观察在Mott绝缘体到超流体量子相变过程中相干性的出现，研究了一个干净且可控的超冷原子设置中的典型例子。 在一维玻色-哈伯德模型中，我们发现实验观测与数值模拟在产生的相干长度方面完全一致。 因此，我们对该强关联系统进行了大量认证的类比量子模拟，超越了自由准粒子的范围。 实验上，我们还探索了高维情况下相干性的出现，因为在这些情况下没有可用的经典模拟，以及负温度的情况。 对于中间淬火速度，我们观察到相干长度的幂律行为，类似于基布尔-祖雷克机制。 然而，我们发现指数强烈依赖于最终的相互作用强度，因此超出了该机制的范围。 显示英文摘要

摘要： The dynamics of quantum phase transitions poses one of the most challenging problems in modern many-body physics. Here, we study a prototypical example in a clean and well-controlled ultracold atom setup by observing the emergence of coherence when crossing the Mott insulator to superfluid quantum phase transition. In the one-dimensional Bose-Hubbard model, we find perfect agreement between experimental observations and numerical simulations for the resulting coherence length. We thereby perform a largely certified analogue quantum simulation of this strongly correlated system reaching beyond the regime of free quasiparticles. Experimentally, we additionally explore the emergence of coherence in higher dimensions where no classical simulations are available, as well as for negative temperatures. For intermediate quench velocities, we observe a power-law behaviour of the coherence length, reminiscent of the Kibble-Zurek mechanism. However, we find exponents that strongly depend on the final interaction strength and thus lie outside the scope of this mechanism.