论文标题
当边界条件有利于这两个阶段之一时，动力学的缩放特性
Scaling properties of the dynamics at first-order quantum transitions when boundary conditions favor one of the two phases
论文作者
论文摘要
当将其一个哈密顿参数之一驱动到一阶量子转换（FOQT）时，我们解决了多体系统的不平衡动力学。特别是，我们认为系统受固定的边界条件的约束，有利于由FOQT隔开的两个阶段之一：更确切地说，有利于相同磁化相（EFBC）或相反阶段（OFBC）在链条的两端的边界条件。这些问题是在范式的一维量子ISing模型中研究的，其中FOQT由纵向磁场h驱动。我们研究了瞬时淬火的动态行为以及在FOQT中h缓慢变化的方案。我们为EFBC和OFBC开发了动态有限尺寸的缩放理论，该理论在中性边界条件的情况下显示出一些显着的差异。在两种情况下，相应的相关时间尺度显示了定性不同的大小依赖性：在EFBC的情况下，它呈指数增加，并且在OFBC的情况下是大小的幂。
We address the out-of-equilibrium dynamics of a many-body system when one of its Hamiltonian parameters is driven across a first-order quantum transition (FOQT). In particular, we consider systems subject to fixed boundary conditions, favoring one of the two phases separated by the FOQT: more precisely, boundary conditions that favor the same magnetized phase (EFBC) or opposite phases (OFBC) at the two ends of the chain. These issues are investigated within the paradigmatic one-dimensional quantum Ising model, in which FOQTs are driven by the longitudinal magnetic field h. We study the dynamic behavior for an instantaneous quench and for a protocol in which h is slowly varied across the FOQT. We develop a dynamic finite-size scaling theory for both EFBC and OFBC, which displays some remarkable differences with respect to the case of neutral boundary conditions. The corresponding relevant time scale shows a qualitative different size dependence in the two cases: it increases exponentially with the size in the case of EFBC, and as a power of the size in the case of OFBC.
