...
首页> 外文期刊>Physical review >First-principles investigation of transient current in molecular devices by using complex absorbing potentials
【24h】

First-principles investigation of transient current in molecular devices by using complex absorbing potentials

机译:利用复杂的吸收势研究分子装置中瞬态电流的第一性原理

获取原文
获取原文并翻译 | 示例
           

摘要

Based on the nonequilibrium Green's function (NEGF) coupled with density function theory (DFT), namely, NEGF-DFT quantum transport theory, we propose an efficient formalism to calculate the transient current of molecular devices under a step-like pulse from first principles. By combining NEGF-DFT with the complex absorbing potential (CAP), the computational complexity of our formalism (NEGF-DFT-CAP) is proportional to O(N) where N is the number of time steps in the time-dependent transient current calculation. Compared with the state-of-the-art algorithm of first-principles time-dependent calculation that scales with at least N~2, this order N technique drastically reduces the computational burden making it possible to tackle realistic molecular devices. We have presented a detailed discussion on how to implement this scheme numerically from first principles. To check the accuracy of our method, we carry out the benchmark calculation compared with NEGF-DFT formalism and they agree well with each other. As an application of this method, we investigate the transient current of a molecular device Al-C_3-Al from first principles.
机译:基于非平衡格林函数(NEGF)以及密度泛函理论(DFT),即NEGF-DFT量子输运理论,我们提出了一种有效的形式主义,是根据第一原理从阶梯状脉冲计算分子器件的瞬态电流的。通过将NEGF-DFT与复数吸收势(CAP)结合使用,我们形式主义的计算复杂度(NEGF-DFT-CAP)与O(N)成比例,其中N是与时间有关的瞬态电流计算中的时间步数。与最先进的第一原理时变算法(至少以N〜2进行缩放)相比,这种N阶技术极大地减少了计算负担,从而有可能解决现实的分子装置。我们已经提出了关于如何从第一原理以数字方式实施该方案的详细讨论。为了检查我们的方法的准确性,我们与NEGF-DFT形式主义进行了基准计算,它们相互之间非常吻合。作为该方法的一种应用,我们从第一原理出发研究了分子装置Al-C_3-Al的瞬态电流。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号