Journal
NEW JOURNAL OF PHYSICS
Volume 14, Issue -, Pages -Publisher
IOP PUBLISHING LTD
DOI: 10.1088/1367-2630/14/11/115027
Keywords
-
Categories
Funding
- European Science Foundation
- EuroHorc
- FAPERJ (Brazil)
- IUF
- National Science Foundation [NSF PHY11-25915]
- French ANR [ANR-08-JCJC-0056-01]
- Agence Nationale de la Recherche (ANR) [ANR-08-JCJC-0056] Funding Source: Agence Nationale de la Recherche (ANR)
Ask authors/readers for more resources
Motivated by the recent discovery of a spin-liquid phase for the Hubbard model on the honeycomb lattice at half-filling (Meng et al 2010 Nature 88 487), we apply both perturbative and non-perturbative techniques to derive effective spin Hamiltonians describing the low-energy physics of the Mottinsulating phase of the system. Exact diagonalizations of the so-derived models on small clusters are performed, in order to assess the quality of the effective low-energy theory in the spin-liquid regime. We show that six-spin interactions on the elementary loop of the honeycomb lattice are the dominant sub-leading effective couplings. A minimal spin model is shown to reproduce most of the energetic properties of the Hubbard model on the honeycomb lattice in its spin-liquid phase. Surprisingly, a more elaborate effective low-energy spin model obtained by a systematic graph expansion rather disagrees beyond a certain point with the numerical results for the Hubbard model at intermediate couplings.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available