A self-consistent perturbative evaluation of ground state energies: application to cohesive energies of spin lattices

Abstract

The work presents a simple formalism which proposes an estimate of the ground state energy from a single reference function. It is based on a perturbative expansion but leads to non linear coupled equations. It can be viewed as well as a modified coupled cluster formulation. Applied to a series of spin lattices governed by model Hamiltonians the method leads to simple analytic solutions. The so-calculated cohesive energies are surprisingly accurate. Two examples illustrate its applicability to locate phase transition.

Accepted by Phys. Rev. B

References in corpus (5)

• Phase diagram of depleted Heisenberg model for CaV4O9
• Plaquette Resonating-Valence-Bond Ground State of CaV${}_4$O${}_9$
• Systematic Inclusion of High-Order Multi-Spin Correlations for the Spin-$\frac{1}{2}$ $XXZ$ Models
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Cited by in corpus (2)

• A renormalized excitonic method in terms of block excitations. Application to spin lattices
• Phase transitions in the Shastry-Sutherland lattice