Abstract
Large-scale Monte Carlo simulations are employed to study phase transitions in the three-dimensional compact Abelian Higgs model in adjoint representations of the matter field, labeled by an integer q, for We also study various limiting cases of the model, such as the lattice gauge theory, dual to the three-dimensional (3D) spin model, and the 3D spin model which is dual to the lattice gauge theory in the limit In addition, for benchmark purposes, we study the square lattice eight-vertex model, which is exactly solvable and features nonuniversal critical exponents. We have computed the first, second, and third moments of the action to locate the phase transition of the compact Abelian Higgs model in the parameter space where is the coupling constant of the matter term and is the coupling constant of the gauge term. We have found that for the three-dimensional compact Abelian Higgs model has a phase-transition line which is first order for below a finite tricritical value and second order above. The first order phase transition persists for finite and joins the second order phase transition at a tricritical point For all other integer we have considered, the entire phase-transition line is critical. We have used finite-size scaling of the second and third moments of the action to extract critical exponents and without invoking hyperscaling, for the model, the spin and lattice gauge models, as well as the compact Abelian Higgs model for and In all cases, we have found that for practical system sizes, the third moment gives scaling of superior quality compared to the second moment. We have also computed the exponent ratio for the compact Higgs model along the critical line, finding a continuously varying ratio as well as continuously varying and as is increased from to with the Ising universality class as a limiting case for and the universality class as a limiting case for However, the critical line exhibits a remarkable resilience of criticality as is reduced along the critical line. Thus, the three-dimensional compact Abelian Higgs model for appears to represent a fixed-line theory defining a new universality class. We relate these results to a recent microscopic description of zero-temperature quantum phase transitions within insulating phases of strongly correlated systems in two spatial dimensions, proposing the above to be the universality class of the zero-temperature quantum phase transition from a Mott-Hubbard insulator to a charge-fractionalized insulator in two spatial dimensions, which thus is that of the 3D Ising model for a considerable range of parameters.
- Received 16 January 2003
DOI:https://doi.org/10.1103/PhysRevB.67.205104
©2003 American Physical Society