论文标题
简单的电流诱导效应方法 - 金属链中的键减弱
Simple approach to current-induced effects -- bond weakening in metal chains
论文作者
论文摘要
我们提出了一种简单的第一原理方案，用于计算非平衡体系系统的机械性能，假设外部电压偏置描述的电子状态具有理想的弹道分布函数。这允许快速计算携带弹道电流的散装系统中电流引起的应力的估计。应力是使用Hellmann-Feynman定理计算的，并且与非平衡自由能的衍生物一致。我们说明了一维金属链的理论和目前的结果。我们发现，屈服应力对施加电压的敏感性与实验中发现的金属之间的断裂电压顺序相符。特别是，在强电流下，黄金被认为是最稳定的，而铝是最不稳定的。
We present a simple, first principles scheme for calculating mechanical properties of nonequilibrium bulk systems assuming an ideal ballistic distribution function for the electronic states described by the external voltage bias. This allows for fast calculations of estimates of the current-induced stresses inside bulk systems carrying a ballistic current. The stress is calculated using the Hellmann-Feynman theorem, and is in agreement with the derivative of the nonequilibrium free energy. We illustrate the theory and present results for one-dimensional (1D) metal chains. We find that the susceptibility of the yield stress to the applied voltage agrees with the ordering of break voltages among the metals found in experiments. In particular, gold is seen to be the most stable under strong current, while aluminum is the least stable.
