Coupled-cluster method: A lattice-path-based subsystem approximation scheme for quantum lattice models

Journal Article · Fri Apr 15 04:00:00 EDT 2011 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.83.042111· OSTI ID:21544567

Bishop, R F; Li, P H. Y. ^[1]

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1. School of Physics and Astronomy, Schuster Building, University of Manchester, Manchester M13 9PL (United Kingdom)

An approximation hierarchy, called the lattice-path-based subsystem (LPSUBm) approximation scheme, is described for the coupled-cluster method (CCM). It is applicable to systems defined on a regular spatial lattice. We then apply it to two well-studied prototypical (spin-(1/2) Heisenberg antiferromagnetic) spin-lattice models, namely, the XXZ and the XY models on the square lattice in two dimensions. Results are obtained in each case for the ground-state energy, the ground-state sublattice magnetization, and the quantum critical point. They are all in good agreement with those from such alternative methods as spin-wave theory, series expansions, quantum Monte Carlo methods, and the CCM using the alternative lattice-animal-based subsystem (LSUBm) and the distance-based subsystem (DSUBm) schemes. Each of the three CCM schemes (LSUBm, DSUBm, and LPSUBm) for use with systems defined on a regular spatial lattice is shown to have its own advantages in particular applications.

• OSTI ID: 21544567
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 4 Vol. 83; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ANGULAR MOMENTUM
ANTIFERROMAGNETISM
APPROXIMATIONS
CALCULATION METHODS
CLUSTER MODEL
CRYSTAL LATTICES
CRYSTAL STRUCTURE
MAGNETISM
MAGNETIZATION
MATHEMATICAL MODELS
MECHANICS
MONTE CARLO METHOD
NUCLEAR MODELS
PARTICLE PROPERTIES
QUANTUM MECHANICS
SERIES EXPANSION
SPIN
SPIN WAVES
TETRAGONAL LATTICES