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A density matrix renormalisation group algorithm for quantum lattice systems with a large number of states per site

R. J. Bursill
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Abstract

A variant of White's density matrix renormalisation group scheme which is designed to compute low-lying energies of one-dimensional quantum lattice models with a large number of degrees of freedom per site is described. The method is tested on two exactly solvable models---the spin-1/2 antiferromagnetic Heisenberg chain and a dimerised XY spin chain. To illustrate the potential of the method, it is applied to a model of spins interacting with quantum phonons. It is shown that the method accurately resolves a number of energy gaps on periodic rings which are sufficiently large to afford an accurate investigation of critical properties via the use of finite-size scaling theory.

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R. J. Bursill. 1998-12-22. A density matrix renormalisation group algorithm for quantum lattice systems with a large number of states per site. https://doi.org/10.1103/physrevb.60.1643

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