论文标题
在一维量子样系统中淬灭后的动力学
Dynamics after quenches in one-dimensional quantum Ising-like systems
论文作者
论文摘要
我们研究了一维量子液样系统的不平衡动力学,这是由于哈密顿参数的突然淬火$ g $驱动量子阶段和有序相之间的量子过渡。特别是,我们考虑到临界值$ g_c $周围的$ g $的淬灭,主要解决量子过渡是否以及如何在这种深层平衡动力学期间的横向和纵向磁化的演变中留下的痕迹。我们阐明了热力学无限尺寸极限中奇异性的出现,这可能与模型的集成性有关。周期性和开放边界条件下的有限系统会形成与复兴现象相关的特殊幂律有限大小的缩放定律,但显然与量子过渡无关,因为它们的主要特征通常在淬灭$ g $的通用值中观察到。我们还研究了与环境的耗散相互作用的影响,该环境由lindblad方程与局部衰减和泵送耗散算子建模,可通过约旦 - 智能映射获得的二次费米子模型。耗散倾向于抑制封闭系统统一动力学的主要特征。最终,由于进一步的晶格相互作用,例如在各向异性的近代邻居Ising(Annni)模型中,我们最终解决了积分破坏的影响。我们表明,后淬火动力学的某些定性特征持续存在,特别是在淬火到量子铁磁和顺磁性相时的不同行为,以及由于系统的有限大小而引起的复兴现象。
We study the out-of-equilibrium dynamics of one-dimensional quantum Ising-like systems, arising from sudden quenches of the Hamiltonian parameter $g$ driving quantum transitions between disordered and ordered phases. In particular, we consider quenches to values of $g$ around the critical value $g_c$, and mainly address the question whether, and how, the quantum transition leaves traces in the evolution of the transverse and longitudinal magnetizations during such a deep out-of-equilibrium dynamics. We shed light on the emergence of singularities in the thermodynamic infinite-size limit, likely related to the integrability of the model. Finite systems in periodic and open boundary conditions develop peculiar power-law finite-size scaling laws related to revival phenomena, but apparently unrelated to the quantum transition, because their main features are generally observed in quenches to generic values of $g$. We also investigate the effects of dissipative interactions with an environment, modeled by a Lindblad equation with local decay and pumping dissipation operators within the quadratic fermionic model obtainable by a Jordan-Wigner mapping. Dissipation tends to suppress the main features of the unitary dynamics of closed systems. We finally address the effects of integrability breaking, due to further lattice interactions, such as in anisotropic next-to-nearest neighbor Ising (ANNNI) models. We show that some qualitative features of the post-quench dynamics persist, in particular the different behaviors when quenching to quantum ferromagnetic and paramagnetic phases, and the revival phenomena due to the finite size of the system.