Hierarchical Liouville-Space Approach for Accurate and Universal Characterization of Quantum Impurity Systems

ZhenHua Li, NingHua Tong, Xiao Zheng, Dong Hou, JianHua Wei, Jie Hu, and YiJing Yan

Phys. Rev. Lett. 109, 266403 – Published 26 December 2012

Abstract

A hierarchical equations of motion based numerical approach is developed for accurate and efficient evaluation of dynamical observables of strongly correlated quantum impurity systems. This approach is capable of describing quantitatively Kondo resonance and Fermi-liquid characteristics, achieving the accuracy of the latest high-level numerical renormalization group approach, as demonstrated on single-impurity Anderson model systems. Its application to a two-impurity Anderson model results in differential conductance versus external bias, which correctly reproduces the continuous transition from Kondo states of individual impurity to singlet spin states formed between two impurities. The outstanding performance on characterizing both equilibrium and nonequilibrium properties of quantum impurity systems makes the hierarchical equations of motion approach potentially useful for addressing strongly correlated lattice systems in the framework of dynamical mean-field theory.

Received 17 June 2012

DOI:https://doi.org/10.1103/PhysRevLett.109.266403

Authors & Affiliations

ZhenHua Li¹, NingHua Tong¹, Xiao Zheng^2,*, Dong Hou², JianHua Wei^1,†, Jie Hu^3,4, and YiJing Yan^2,3,‡

¹Department of Physics, Renmin University of China, Beijing 100872, China
²Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China
³Department of Chemistry, Hong Kong University of Science and Technology, Hong Kong, China
⁴Department of Physics, Capital Normal University, Beijing 100048, China