Insights into the structure of many-electron wave functions of Mott-insulating antiferromagnets: The three-band Hubbard model in full configuration interaction quantum Monte Carlo

Lauretta R. Schwarz, George H. Booth, and Ali Alavi
Phys. Rev. B 91, 045139 – Published 30 January 2015

Abstract

We investigate the ground-state wave function of a prototypical strongly correlated system, a three-band (pd) Hubbard model of cuprates, using full configuration interaction quantum Monte Carlo. We show that the configuration interaction description of the exact ground state wave function is profoundly affected by the choice of single-particle representation, in a counterintuitive manner. Thus a broken-symmetry unrestricted Hartree-Fock basis, which at a single configuration level produces a qualitatively correct description of the antiferromagnet, results in a highly entangled exact solution consisting of high particle-hole excitations of the reference. This wave function is found to be very difficult to approximate using subspace diagonalizations. Conversely, a restricted Hartree-Fock basis, which yields at a single configuration level a qualitatively incorrect paramagnetic metal, results in a relatively rapidly converging configuration interaction expansion. Convergence can be further accelerated by adopting a natural orbital representation. Our results suggest that with the correct single-particle basis, such strongly correlated systems may be described by relatively compact wave functions.

  • Figure
  • Figure
  • Figure
  • Received 29 August 2014

DOI:https://doi.org/10.1103/PhysRevB.91.045139

©2015 American Physical Society

Authors & Affiliations

Lauretta R. Schwarz1, George H. Booth1,2, and Ali Alavi1,3

  • 1University of Cambridge, Chemistry Department, Lensfield Road, Cambridge CB2 1EW, United Kingdom
  • 2King's College London, Theory and Simulation of Condensed Matter, The Strand, London WC2R 2LS, United Kingdom
  • 3Max Planck Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 91, Iss. 4 — 15 January 2015

Reuse & Permissions
Access Options
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review B

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×