论文标题
旋转玻璃体冷凝物中的动态量子相变和关键性增强了量子感应
Dynamical quantum phase transitions in a spinor Bose-Einstein condensate and criticality enhanced quantum sensing
论文作者
论文摘要
量子相转变普遍存在于量子多体系统的地面和激发状态，并且它们与非平衡动力学相变的无密切关系，但是识别却很具有挑战性。在Spin-1 Bose-Einstein冷凝物的系统中，尽管已经探测了与基态和最上方激发态的平衡相变的动力学相变，但迄今为止，在中间激发态中发生的情况仍未受到影响。在这里，我们阐明了旋转冷凝物中的地面和激发态量子相变，可以诊断为动力学相变。根据量子Fisher信息，披露了系统的平衡相变和非平衡行为之间的联系。我们还证明，可以实现超出标准量子限制的接近临界点参数估计。这项工作不仅可以通过一种可以立即应用于一类少数模式量子系统的方案来探索激发态量子相变的探索，而且还提供了有关量子关键性和量子增强感测之间关系的新观点。
Quantum phase transitions universally exist in the ground and excited states of quantum many-body systems, and they have a close relationship with the nonequilibrium dynamical phase transitions, which however are challenging to identify. In the system of spin-1 Bose-Einstein condensates, though dynamical phase transitions with correspondence to equilibrium phase transitions in the ground state and uppermost excited state have been probed, those taken place in intermediate excited states remain untouched in experiments thus far. Here we unravel that both the ground and excited-state quantum phase transitions in spinor condensates can be diagnosed with dynamical phase transitions. A connection between equilibrium phase transitions and nonequilibrium behaviors of the system is disclosed in terms of the quantum Fisher information. We also demonstrate that near the critical points parameter estimation beyond standard quantum limit can be implemented. This work not only advances the exploration of excited-state quantum phase transitions via a scheme that can immediately be applied to a broad class of few-mode quantum systems, but also provides new perspective on the relationship between quantum criticality and quantum enhanced sensing.
