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arXiv · 2401.15000

Density-matrix renormalization group algorithm for non-Hermitian systems

Peigeng Zhong·Wei Pan·Haiqing Lin·Xiaoqun Wang·Shijie Hu
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Abstract

A biorthonormal-block density-matrix renormalization group algorithm is proposed to accurately compute properties of large-scale non-Hermitian many-body systems, in which a renormalized-space partition of the non-Hermitian reduced density matrix is implemented to fulfill the prerequisite for the biorthonormality of the renormalization group (RG) transformation and to optimize the construction of saved Hilbert spaces. A redundancy in saved spaces of the reduced density matrix is exploited to reduce a condition number resulting from the non-unitarity of the left and right transformation matrices, in order to ensure the numerical stability of the RG procedure. The algorithm is successfully applied to an interacting fermionic Su-Schrieffer-Heeger model with nonreciprocal hoppings and staggered complex chemical potential, exhibiting novel many-body phenomena.

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Peigeng Zhong, Wei Pan, Haiqing Lin, Xiaoqun Wang, Shijie Hu. 2024-01-26. Density-matrix renormalization group algorithm for non-Hermitian systems. https://arxiv.org/abs/2401.15000

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