Two-Site shift Product Wave Function Renormalization Group Method Applied to Quantum Systems

TL;DR

This paper introduces a 2-site shift PWFRG method that improves wave function estimation for quantum systems in both finite and infinite DMRG algorithms, enhancing accuracy in the thermodynamic limit.

Contribution

The paper presents a novel 2-site shift PWFRG algorithm that improves wave function estimation for quantum systems with 2-site modulation in DMRG.

Findings

The 2-site shift PWFRG outperforms previous methods in the thermodynamic limit.

The method effectively handles 2-site modulation in both finite and infinite algorithms.

Improved wave function estimation leads to better accuracy in quantum system simulations.

Abstract

We report a way of wave function estimation for the density matrix renormalization group (DMRG) method applied to quantum systems, which has 2-site modulation, when the system size extension is necessary in both the finite and the infinite algorithms. The estimation is performed by renormalization group (RG) transformation applied to the ground state wave function, which is represented as the matrix product. This RG scheme is known as the product wave function renormalization group (PWFRG) method. In order to treat the 2-site modulation, the operation of the RG transformation is shifted by amount of 2 lattice sites. It turns out that this 2-site shift algorithm provides better wave function estimation in the thermodynamic limit, compared with the previously known PWFRG algorithm.