We study both mean-field and full quantum dynamics of symmetry-breaking transitions (SBTs) in a coupled two-component Bose-Einstein condensate. By controlling s-wave scattering lengths and coupling strength, it is possible to stimulate SBTs between normal and spontaneously polarized ground states. In static transitions, the probability maxima of full quantum ground states correspond to the mean-field ground states. In dynamical transitions, due to the vanishing of excitation gaps, the mean-field dynamics shows universal scalings obeying Kibble-Zurek mechanism. Both mean-field and full quantum defect modes appear as damped oscillations, but they appear at different critical points and undergo different oscillation regimes. The anomalous breakdown of mean-field dynamics induced by SBTs depends on the approaching direction.
我们发现，肮脏的量子霍尔系统在其边缘表现出大的流体动力学波动，导致在Kardar-Parisi-Zhang普适性类$ω\simeq ck - i \mathcal D k^{3/2} $中的阻尼电荷激发。边缘的耗散光学电导率在低频$σ(ω) \sim 1/ω^{1/3}$处是奇异的。这些结果是直接后果的电荷连续性关系，手征异常，和热化的边缘-特别是平移不变性是不假定的。热的扩散也同样会破裂，其普适性取决于体热霍尔电导率是否消失。我们进一步建立了表面手性金属的波动流体力学理论，其中电荷波动对输运进行了对数修正。
Crossing over universal scaling laws in two-dimensional driven dissipative condensates
Université Paris-Saclay, CNRS, Centre de Nanosciences et de Nanotechnologies (C2N)（巴黎萨克雷大学，法国国家科学研究中心，纳米科学与技术中心）；TQC, Universiteit Antwerpen（安特卫普大学量子计算组）；Univ. Grenoble Alpes and CNRS, Laboratoire de Physique et Modélisation des Milieux Condensés（格勒诺布尔阿尔卑斯大学与法国国家科学研究中心，凝聚态物质物理与建模实验室）
