Nash, Charles and O'Connor, Denjoe (2016) Dimer geometry, amoebae and a vortex dimer model. Journal of Physics A: Mathematical and Theoretical, 50 (35). p. 355002. ISSN 17518113

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Abstract
We present a geometrical approach for studying dimers. We introduce a connection for dimer problems on bipartite and nonbipartite graphs. In the bipartite case the connection is flat but has nontrivial Z_2 holonomy round certain curves. This holonomy has the universality property that it does not change as the number of vertices in the fundamental domain of the graph is increased. It is argued that the Ktheory of the torus, with or without punctures, is the appropriate underlying invariant. In the nonbipartite case the connection has nonzero curvature as well as nonzero Chern number. The curvature does not require the introduction of a magnetic field. The phase diagram of these models is captured by what is known as an amoeba. We introduce a dimer model with negative edge weights that give rise to vortices. The amoebae for various models are studied with particular emphasis on the case of negative edge weights which corresponds to the presence of vortices. Vortices gives rise to new kinds of amoebae with certain singular structures which we investigate. On the amoeba of the vortex full hexagonal lattice we find the partition function corresponds to that of a massless Dirac doublet.
Item Type:  Article 

Divisions:  School of Theoretical Physics > Preprints 
Date Deposited:  05 Oct 2017 19:30 
Last Modified:  26 Jul 2018 11:00 
URI:  http://dair.dias.ie/id/eprint/342 
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