Wang Lei, Hu Bambi, Li Baowen
Department of Physics, Renmin University of China, Beijing 100872, People's Republic of China.
Phys Rev E Stat Nonlin Soft Matter Phys. 2012 Oct;86(4 Pt 1):040101. doi: 10.1103/PhysRevE.86.040101. Epub 2012 Oct 4.
Heat conduction in three two-dimensional (2D) momentum-conserving nonlinear lattices are numerically calculated via both nonequilibrium heat-bath and equilibrium Green-Kubo algorithms. It is expected by mainstream theories that heat conduction in such 2D lattices is divergent and the thermal conductivity κ increases with lattice length N logarithmically. Our simulations for the purely quartic lattice firmly confirm it. However, very robust finite-size effects are observed in the calculations for the other two lattices, which well explain some existing studies and imply the extreme difficulties in observing their true asymptotic behaviors with affordable computation resources.
通过非平衡热浴算法和平衡格林 - 库博算法，对三种二维（2D）动量守恒非线性晶格中的热传导进行了数值计算。主流理论预期，此类二维晶格中的热传导是发散的，热导率κ随晶格长度N呈对数增长。我们对纯四次晶格的模拟结果有力地证实了这一点。然而，在对另外两种晶格的计算中观察到了非常显著的有限尺寸效应，这很好地解释了一些现有研究，并意味着用可承受的计算资源观察它们真正的渐近行为极其困难。
