Effective models for gapped phases of strongly correlated quantum lattice models
Yang HY, Schmidt KP (2011)
Publication Status: Published
Publication Type: Journal article
Publication year: 2011
Journal
Publisher: EPL ASSOCIATION, EUROPEAN PHYSICAL SOCIETY
Book Volume: 94
Journal Issue: 1
DOI: 10.1209/0295-5075/94/17004
Abstract
We present a robust scheme to derive effective models non-perturbatively for quantum lattice models when at least one degree of freedom is gapped. A combination of graph theory and the method of continuous unitary transformations (gCUTs) is shown to efficiently capture all zero-temperature fluctuations in a controlled spatial range. The gCUT can be used either for effective quasi-particle descriptions or for effective low-energy descriptions in case of infinitely degenerate subspaces. We illustrate the method for 1d and 2d lattice models yielding convincing results in the thermodynamic limit. We find that the recently discovered spin liquid in the Hubbard model on the honeycomb lattice lies outside the perturbative strong-coupling regime. Various extensions and perspectives of the gCUT are discussed. Copyright (C) EPLA, 2011
Authors with CRIS profile
Involved external institutions
Germany (DE)How to cite
APA:
Yang, H.Y., & Schmidt, K.P. (2011). Effective models for gapped phases of strongly correlated quantum lattice models. EPL - Europhysics Letters, 94(1). https://doi.org/10.1209/0295-5075/94/17004
MLA:
Yang, H. Y., and Kai Phillip Schmidt. "Effective models for gapped phases of strongly correlated quantum lattice models." EPL - Europhysics Letters 94.1 (2011).
BibTeX: Download