Density matrix renormalization group algorithms for Y-junctions

TL;DR

This paper introduces a significantly more efficient density matrix renormalization group algorithm tailored for Y-junction systems, enabling better numerical studies of their quantum properties and potential applications in nanoscale devices.

Contribution

The authors develop a novel, more efficient DMRG algorithm specifically designed for Y-junction geometries, improving computational performance over existing methods.

Findings

Successful application to S=1/2 bound states in Heisenberg S=1 junctions

Comparison of two junction geometries: single site and triangle

Enhanced numerical efficiency for Y-junction systems

Abstract

Systems of Y-junctions are interesting both from a fundamental viewpoint and because of their potential use in nanoscale devices. These systems can be studied numerically with the density matrix renormalization group(DMRG), but existing algorithms are inefficient. Here, we introduce a much more efficient DMRG algorithm for Y-junction systems. As an example of the use of this method, we study $S=1/2$ bound states in Heisenberg S=1 junctions with two geometries, one where the junction consists of a single site, and the other where it consists of a triangle of three sites.