论文标题
绿色的单分子连接功能方法
Green's function methods for single molecule junctions
论文作者
论文摘要
我们对理论绿色的功能方法进行了简短的教学综述，该方法一般而言，尤其是单个分子连接。我们简要描述了分子电子学的实验进步，然后讨论不同的理论方法。然后，我们专注于Green的功能方法。有关物理学的两个特征能量尺度是连接内的多体相互作用，以及分子接触耦合。因此，我们讨论了弱相互作用和弱耦合，因为可以方便地处理标准的非平衡绿色功能（NEGF）方法及其多体风味（假粒子和Hubbard negf）的两个限制。我们认为，两个能量尺度是可比的中间状态，在许多情况下可以在最近引入的超级扰动双重费用方法中有效治疗。最后，我们审查了超越这些分析上可访问限制的方法，这是基于格林功能的数值精确方法的最新发展所体现的。
We present a brief pedagogical review of theoretical Green's function methods applicable to open quantum systems out of equilibrium in general, and single molecule junctions in particular. We briefly describe experimental advances in molecular electronics, then discuss different theoretical approaches. We then focus on Green's function methods. Two characteristic energy scales governing the physics are many-body interactions within the junctions, and molecule-contact coupling. We therefore discuss weak interactions and weak coupling, as two limits that can be conveniently treated within, respectively, the standard nonequilibrium Green's function (NEGF) method and its many-body flavors (pseudoparticle and Hubbard NEGF). We argue that the intermediate regime, where the two energy scales are comparable, can in many cases be efficiently treated within the recently introduced superperturbation dual fermion approach. Finally, we review approaches for going beyond these analytically accessible limits, as embodied by recent developments in numerically exact methods based on Green's functions.
