Crossover in the slow decay of dynamic correlations in the lorentz model.
Crossover in the slow decay of dynamic correlations in the lorentz model.
复制标题
洛伦兹模型中动态相关性缓慢衰减的交叉。
DOI：
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发表时间：
2007
影响因子：
8.6
通讯作者：
T. Franosch
中科院分区：
文献类型：
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作者：
F. Höfling;T. Franosch
用分子动力学模拟方法研究了二维和三维空间非均匀介质模型中输运系数的长时间行为。的速度自相关函数的行为是合理的竞争的临界松弛，由于底层的渗流过渡和流体动力学幂律异常。在二维和在扩散模式的情况下，由于捕获的另一个幂律异常被发现与指数-3而不是-2。此外，伯内特系数的对数发散在稀释极限中得到证实;然而，在有限密度下，它由更强的发散主导。
The long-time behavior of transport coefficients in a model for spatially heterogeneous media in two and three dimensions is investigated by molecular dynamics simulations. The behavior of the velocity autocorrelation function is rationalized in terms of a competition of the critical relaxation due to the underlying percolation transition and the hydrodynamic power-law anomalies. In two dimensions and in the absence of a diffusive mode, another power-law anomaly due to trapping is found with an exponent -3 instead of -2. Further, the logarithmic divergence of the Burnett coefficient is corroborated in the dilute limit; at finite density, however, it is dominated by stronger divergences.