Liao Wenshan, Li Nianbei
Institute of Systems Science and Department of Physics, College of Information Science and Engineering, Huaqiao University, Xiamen 361021, China.
Phys Rev E. 2019 Jun;99(6-1):062125. doi: 10.1103/PhysRevE.99.062125.
The energy diffusion in one-dimensional (1D) momentum conserving nonlinear lattices usually exhibits anomalous superdiffusion, except the coupled rotator lattice with symmetric and periodic interacting potential which has normal energy diffusion corresponding to normal heat conduction. For nonperiodic 1D lattices with momentum conservation, it has been argued that the asymmetric potential can induce normal heat conduction. Later results indicate the observed normal behavior might be the finite size effect and the anomalous behavior will appear in the thermodynamical limit. Here we propose asymmetric and periodic 1D nonlinear lattices with momentum conservation. The energy and momentum diffusion behaviors will be investigated in detail and the same normal diffusion behaviors for both energy and momentum can be observed. These results confirm that the periodicity is the key for normal transport behavior in 1D momentum conserving lattices, whether the potential is symmetric or asymmetric.
在一维（1D）动量守恒非线性晶格中的能量扩散通常表现出反常超扩散，除了具有对称和周期性相互作用势的耦合转子晶格，其具有对应于正常热传导的正常能量扩散。对于具有动量守恒的非周期性一维晶格，有人认为不对称势可以诱导正常热传导。后来的结果表明，观察到的正常行为可能是有限尺寸效应，而反常行为将出现在热力学极限中。在这里，我们提出了具有动量守恒的不对称和周期性一维非线性晶格。将详细研究能量和动量扩散行为，并且可以观察到能量和动量的相同正常扩散行为。这些结果证实，周期性是一维动量守恒晶格中正常输运行为的关键，无论势是对称的还是不对称的。
