Macroscopic effects of localised measurements in jammed states of quantum spin chains

量子阻塞将量子力学带到宏观尺度

Quantum jamming brings quantum mechanics to macroscopic scales

研究具有动力学约束的量子自旋链中的量子阻塞现象，发现局部解阻塞扰动下的动力学可通过非局域映射在宏观尺度展现准粒子散射、束缚态形成等现象，甚至将直积态转变为宏观量子态。

阻塞固体的应力响应：预应力与屏蔽

Stress Response of Jammed Solids: Prestress and Screening

本研究扩展了无序系统的“仅应力”规范理论表述，引入尺度依赖屏蔽以同时捕获介电和Debye型行为，发现软球堆积中特征长度由颗粒尺寸决定，并证明无摩擦阻塞转变附近无Debye型屏蔽，且无序平均下类介电响应持续存在。

Critical dynamics of classical systems under slow quench

We study the slow quench dynamics of a one-dimensional nonequilibrium lattice gas model which exhibits a phase transition in the stationary state between a fluid phase with homogeneously distributed particles and a jammed phase with a macroscopic hole cluster. Our main result is that in the critical region ({\it i.e.}, at the critical point and in its vicinity) where the dynamics are assumed to be frozen in the standard Kibble-Zurek argument, the defect density exhibits an algebraic decay in the inverse annealing rate with an exponent that can be understood using critical coarsening dynamics. …

A numerical investigation of the jamming transition in traffic flow on diluted planar networks

In order to develop a toy model for car's traffic in cities, in this paper we analyze, by means of numerical simulations, the transition among fluid regimes and a congested jammed phase of the flow of "kinetically constrained" hard spheres in planar random networks similar to urban roads. In order to explore as timescales as possible, at a microscopic level we implement an event driven dynamics as the infinite time limit of a class of already existing model (e.g. "Follow the Leader") on an Erdos-Renyi two dimensional graph, the crossroads being accounted by standard Kirchoff density conservati…

Measurement catastrophe and ballistic spread of charge density with vanishing current

One of the features of many-body quantum systems with Hilbert-space fragmentation is the existence of stationary states manifesting quantum jamming. It was recently shown that these are "states with memory", in which, e.g., measuring a localised observable has everlasting macroscopic effects. We study such a measurement catastrophe with an example that stands out for its clarity. We show in particular that at late times the expectation value of a charge density becomes a nontrivial function of the ratio between distance and time notwithstanding the corresponding current approaching zero.

Critical dynamics of the jamming transition in one-dimensional nonequilibrium lattice-gas models

We consider several one-dimensional driven lattice gas models that show a phase transition in the stationary state between a high-density fluid phase in which the particles are homogeneously distributed and a low-density jammed phase where a hole cluster of macroscopic length forms in front of a particle. Using a hydrodynamic equation for an interface growth model obtained from the driven lattice gas models of interest here, we find that in the fluid phase, the roughness exponent and the dynamic exponent that, respectively, characterise the scaling of the saturation width and the relaxation ti…