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arXiv · 2001.02926

Block-Lanczos density-matrix renormalization-group approach to spin transport in Heisenberg chains coupled to leads

F. Lange·S. Ejima·T. Shirakawa·S. Yunoki·H. Fehske
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Abstract

We adapt the block-Lanczos density-matrix renormalization-group technique to study the spin transport in a spin chain coupled to two non-interacting fermionic leads. As an example, we consider leads described by two-dimensional tight-binding models on a square lattice. Although the simulations are carried out using a chain representation of the leads, observables in the original two-dimensional lattice can be calculated by reversing the block-Lanczos transformation. This is demonstrated for leads with Rashba spin-orbit coupling.

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F. Lange, S. Ejima, T. Shirakawa, S. Yunoki, H. Fehske. 2020-01-09. Block-Lanczos density-matrix renormalization-group approach to spin transport in Heisenberg chains coupled to leads. https://doi.org/10.7566/jpsj.89.044601

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