We study universal properties of Abelian gauge theories of quantum antiferromagnets. In this context, we derive an exact relation in d spacetime dimensions between the critical gauge coupling and the...
Nogueira, Flavio S., Nussinov, Zohar
We derive an extended lattice gauge theory type action for quantum dimer models and relate it to the height representations of these systems. We examine the system in two and three dimensions and...
Deconfined quantum criticality driven by Dirac fermions in SU(2) antiferromagnets (2008)
Quantum electrodynamics in 2+1 dimensions is an effective gauge theory for the so called algebraic quantum liquids. A new type of such a liquid, the algebraic charge liquid, has been proposed...
Quantum critical scaling behavior of deconfined spinons (2007)
Nogueira, Flavio S., Kragset, Steinar, Sudbo, Asle
We perform a renormalization group analysis of some important effective field theoretic models for deconfined spinons. We show that deconfined spinons are critical for an isotropic SU(N) Heisenberg...
Nogueira, Flavio S., Kleinert, Hagen
We discuss compact (2+1)-dimensional Maxwell electrodynamics coupled to fermionic matter with N replica. For large enough N, the latter corresponds to an effective theory for the nearest neighbor...
Eremin, Ilya, Nogueira, Flavio S., Tarento, Rene-Jean
We consider the spin and charge Josephson current between two non-uniform Fulde-Ferrel-Larkin-Ovchinnikov superconductors with helimagnetic order. We demonstrate that the presence of the helimagnetic...
Thermally induced rotons in two-dimensional dilute Bose gases (2005)
Nogueira, Flavio S., Kleinert, Hagen
We show that roton-like excitations are thermally induced in a two-dimensional dilute Bose gas as a consequence of the strong phase fluctuations in two dimensions. At low momentum, the roton-like...
Nogueira, Flavio S., Kleinert, Hagen
Compact quantum electrodynamics in 2+1 dimensions often arises as an effective theory for a Mott insulator, with the Dirac fermions representing the low-energy spinons. An important and controversial...
Critical dynamics, duality, and the exact dynamic exponent in extreme type II superconductors (2003)
Nogueira, Flavio S., Manske, Dirk
The critical dynamics of superconductors is studied using renormalization group and duality arguments. We show that in extreme type II superconductors the dynamic critical exponent is given exactly...
Nogueira, Flavio S., Sudbo, Asle
We propose a mechanism by which electric charges deconfine in an Abelian Higgs model with matter fields belonging to the fundamental representation of the gauge group. Kosterlitz-Thouless like...
Field Theoretical Approaches to the Superconducting Phase Transition (2003)
Nogueira, Flavio S., Kleinert, Hagen
Several field theoretical approaches to the superconducting phase transition are discussed. Emphasis is given to theories of scaling and renormalization group in the context of the Ginzburg-Landau...
Spin Josephson effect in ferromagnet/ferromagnet tunnel junctions (2003)
Nogueira, Flavio S., Bennemann, Karl-Heinz
We consider the tunnel spin current between two ferromagnetic metals from a perspective similar to the one used in superconductor/superconductor tunnel junctions. We use fundamental arguments to...
Kosterlitz-Thouless-like deconfinement mechanism in the 2+1 dimensional Abelian Higgs model (2002)
Kleinert, Hagen, Nogueira, Flavio S., Sudbo, Asle
We point out that the permanent confinement in a compact 2+1-dimensional U(1) Abelian Higgs model is destroyed by matter fields in the fundamental representation. The deconfinement transition is...
Kleinert, Hagen, Nogueira, Flavio S., Sudbo, Asle
It is shown that permanent confinement in three-dimensional compact U(1) gauge theory can be destroyed by matter fields in a deconfinement transition. This is a consequence of a non-trivial infrared...
Critical behavior of Ginzburg-Landau model coupled to massless Dirac fermions (2001)
Kleinert, Hagen, Nogueira, Flavio S.
We point out interesting effects of additional massless Dirac fermions with N_F colors upon the critical behavior of the Ginzburg-Landau model. For increasing N_F, the model is driven into the type...
Large N study of extreme type II superconductors in a magnetic field (2001)
De Calan, Claude, Malbouisson, Adolfo P. C., Nogueira, Flavio S.
The large N analysis of an extreme type II superconductor is revisited. It is found that the phase transition is of second-order in dimensions 4 < d < 6. For the physical dimension d=3 no sign of...
Duality and self-duality in Ginzburg-Landau theory with Chern-Simons term (2001)
Kleinert, Hagen, Nogueira, Flavio S.
We derive the exact dual theory of a lattice Ginzburg-Landau theory with an additional topological Chern-Simons (CS) term. It is shown that in the zero-temperature limit, the statistical parameter...
Two different scaling regimes in Ginzburg-Landau model with Chern-Simons term (2001)
Kleinert, Hagen, Nogueira, Flavio S.
The Ginzburg-Landau model with a Chern-Simons term is shown to possess two different scaling regimes depending on whether the mass of the scalar field is zero or not. In contrast to pure $\phi^4$...
Anomalous dimensions and phase transitions in superconductors (2000)
The anomalous scaling in the Ginzburg-Landau model for the superconducting phase transition is studied. It is argued that the negative sign of the $\eta$ exponent is a consequence of a special...
De Calan, Claude, Nogueira, Flavio S.
An unifying scenario for the critical behavior of YBa$_{2}$Cu$_{3}$O$_{7-\delta}$ (YBCO) and Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+\delta}$ (BSCCO) is proposed. It is shown that both critical crossovers...
The superconducting phase transition and gauge dependence (1999)
De Calan, Claude, Nogueira, Flavio S.
The gauge dependence of the renormalization group functions of the Ginzburg-Landau model is investigated. The analysis is done by means of the Ward-Takahashi identities. After defining the local...
The superconducting order parameter and gauge dependence (1999)
De Calan, Claude, Nogueira, Flavio S.
The gauge dependence of the renormalization group functions of the Ginzburg-Landau model is investigated. The analysis is done by means of the Ward-Takahashi identities. After defining the...
Non-perturbative evolution equations for the tricritical theory (1996)
The N component scalar tricritical theory is considered in a non-perturbative setting. We derive non-perturbative beta functions for the relevant couplings in $d\leq 3$. The beta functions are...
Study of a toy model and its relation to the Hubbard model with infinite range hopping (1995)
Nogueira, Flavio S., Anda, Enrique V.
A toy model of strongly correlated fermions is studied using Green function and functional integration methods. The model exhibits a metal-insulator transition as the interaction is varied. In the...