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arXiv 0809.0453cond-mat.stat-mechmath-phmath.MPnlin.CD
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反常热输运的一个随机模型:稳态的解析解

A stochastic model of anomalous heat transport: analytical solution of the steady state

Stefano Lepri, Carlos Mejia-Monasterio, Antonio Politi

摘要:

我们考虑一个一维谐振晶体与保守噪声,在接触两个随机Langevin热浴在不同的温度。噪声项由相邻振子之间的碰撞组成,它们以$γ$的速率交换动量。协方差矩阵的稳态方程在热力学极限($N\to\infty$)中精确求解。特别是,我们推导出的温度分布,这原来是独立的$γ$的解析表达式。此外,我们还得到了能流首项的精确表达式,其标度为$1/\sqrt{γN}$。我们的理论结果与有限$N$协方差矩阵的数值解是一致的。

英文摘要:

We consider a one-dimensional harmonic crystal with conservative noise, in contact with two stochastic Langevin heat baths at different temperatures. The noise term consists of collisions between neighbouring oscillators that exchange their momenta, with a rate $γ$. The stationary equations for the covariance matrix are exactly solved in the thermodynamic limit ($N\to\infty$). In particular, we derive an analytical expression for the temperature profile, which turns out to be independent of $γ$. Moreover, we obtain an exact expression for the leading term of the energy current, which scales as $1/\sqrt{γN}$. Our theoretical results are finally found to be consistent with the numerical solutions of the covariance matrix for finite $N$.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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