论文标题
约瑟夫森结数组中的弱点破裂
Weak ergodicity breaking in Josephson-junction arrays
论文作者
论文摘要
我们研究约瑟夫森连接阵列的量子动力学。我们发现，即使约瑟夫森相互作用足以破坏多重组中的频谱组织，并且不再有可能破坏频谱的组织。这些本征态提供了弱的牙齿破裂，并让人联想到量子疤痕。由于存在这些本征态，并以电荷密度波状态初始化，因此系统不会热量化，并且电荷密度波顺序持续很长时间。考虑到全局的急性探针，我们发现该系统倾向于增加系统尺寸：参数范围，其中大部分本征状态看起来是非共生的收缩，以增加系统尺寸。我们研究两个几何形状，一个一维链和一个两腿梯。在后一种情况下，添加磁通量会使系统更加颈。
We study the quantum dynamics of Josephson junction arrays. We find isolated groups of low-entanglement eigenstates, that persist even when the Josephson interaction is strong enough to destroy the organization of the spectrum in multiplets, and a perturbative description is no longer possible. These eigenstates provide a weak ergodicity breaking, and are reminiscent of the quantum scars. Due to the presence of these eigenstates, initializing with a charge-density-wave state, the system does not thermalize and the charge-density-wave order persists for long times. Considering global ergodicity probes, we find that the system tends towards more ergodicity for increasing system size: The parameter range where the bulk of the eigenstates look nonergodic shrinks for increasing system size. We study two geometries, a one-dimensional chain and a two-leg ladder. In the latter case, adding a magnetic flux makes the system more ergodic.
