论文标题
二维电网中的异常分形缩放
Anomalous fractal scaling in two-dimensional electric networks
论文作者
论文摘要
物理系统的许多定性性质可以从系统尺寸的尺度缩放的方式来预测。与连续性期望相反,我们观察到与对数缩放的偏差,在二维$ LC $电路网络的阻抗中。我们发现,这种异常的阻抗对敏感的贡献取决于节点的数量$ n $以奇怪的不稳定方式,并且在实验上证明了其对单个组件的接触和寄生阻抗的扰动的鲁棒性。这种阻抗异常可追溯到磁场中的Harper方程的普遍共振条件,即使我们的电路网络不涉及磁翻译对称性。它表现出不同$ n $的异常阻抗峰的新兴分形参数结构,这与连续理论无法核对,并且不对应于常规的波导共振行为。每当同时存在共振频率尺度时,这种异常的分形尺度扩展到网络laplacian所描述的通用系统的传输属性。
Much of the qualitative nature of physical systems can be predicted from the way it scales with system size. Contrary to the continuum expectation, we observe a profound deviation from logarithmic scaling in the impedance of a two-dimensional $LC$ circuit network. We find this anomalous impedance contribution to sensitively depend on the number of nodes $N$ in a curious erratic manner, and experimentally demonstrate its robustness against perturbations from the contact and parasitic impedance of individual components. This impedance anomaly is traced back to a generalized resonance condition reminiscent of the Harper's equation for electronic lattice transport in a magnetic field, even though our circuit network does not involve magnetic translation symmetry. It exhibits an emergent fractal parametric structure of anomalous impedance peaks for different $N$ that cannot be reconciled with continuum theory and does not correspond to regular waveguide resonant behavior. This anomalous fractal scaling extends to the transport properties of generic systems described by a network Laplacian whenever a resonance frequency scale is simultaneously present.