论文标题
有限时间动力学转换的兰道理论
Landau theory for finite-time dynamical phase transitions
论文作者
论文摘要
我们研究了热力学可观察物的时间演变，这些观察力表征了瞬时温度淬火后热弛豫的耗散性质。结合了随机热力学和大驱动理论的工具，我们开发了一种强大的理论，用于计算这种可观察物的大差异统计。我们的方法自然会导致描述动态兰道理论，这是一种用于分析有限时间动态相变的多功能工具。相关的Landau电位的拓扑允许对动态阶参数和相图的明确识别。作为我们方法的立即应用，我们表明，平均场自旋模型和环境之间热交换的概率分布表现出由有限的时间动力学相变引起的单数点，一个扭结。使用我们的兰道理论，我们对相变的详细研究进行了详细的研究。尽管新转变的表现与磁化中先前发现的有限时间跃迁的表现相似，但两者的性质和动力学起源却大不相同。
We study the time evolution of thermodynamic observables that characterise the dissipative nature of thermal relaxation after an instantaneous temperature quench. Combining tools from stochastic thermodynamics and large-deviation theory, we develop a powerful theory for computing the large-deviation statistics of such observables. Our method naturally leads to a description in terms of a dynamical Landau theory, a versatile tool for the analysis of finite-time dynamical phase transitions. The topology of the associated Landau potential allows for an unambiguous identification of the dynamical order parameter and of the phase diagram. As an immediate application of our method, we show that the probability distribution of the heat exchanged between a mean-field spin model and the environment exhibits a singular point, a kink, caused by a finite-time dynamical phase transition. Using our Landau theory, we conduct a detailed study of the phase transition. Although the manifestation of the new transition is similar to that of a previously found finite-time transition in the magnetisation, the properties and the dynamical origins of the two turn out to be very different.
