Related papers: Chern-Simons superconductors and their instabiliti…
Topological superconductors are characterized by topological invariants that describe the number and nature of their robust boundary modes. These invariants must also have observable consequences in the bulk of the system, akin to the…
We consider 2+1 dimensional noncommutative models of scalar and fermionic fields coupled to the Chern-Simons field. We show that, at least up to one loop, the model containing only a fermionic field in the fundamental representation…
Correlation effects in CuO$_2$ layers give rise to a complicated landscape of collective excitations in high-T$_{\rm c}$ cuprates. Their description requires an accurate account for electronic fluctuations at a very broad energy range and…
We investigate the interplay between lattice-symmetry breaking and superconducting order in a two-dimensional model of doped antiferromagnets, with long-range Coulomb interactions and Sp(2N) spin symmetry, in the large-N limit. Our results…
A comprehensive theory for electronic transport in itinerant ferromagnets is developed. We first show that the Q-field theory used previously to describe a disordered Fermi liquid also has a saddle-point solution that describes a…
We investigate the magnetic ground state and phase transitions in the frustrated three-dimensional system CaMn2P2 using first-principles calculations combined with spin-dynamics simulations. Our DFT+U calculations reveal that CaMn2P2…
Fully gapped two-dimensional superconductors coupled to dynamical electromagnetism are known to exhibit topological order. In this work, we develop a unified low-energy description for spin-singlet paired states by deriving topological…
The heavy fermion superconductor CeCoIn_5 can be tuned between superconducting and antiferromagnetic ground states by hole doping with Cd. Nuclear magnetic resonance (NMR) data indicate that these two orders coexist microscopically with an…
We report a study on the interplay between antiferromagnetism (AFM) and superconductivity (SC) in a heavy-fermion compound CeRhIn$_5$ under pressure $P=1.75$ GPa. The onset of the magnetic order is evidenced from a clear split of…
A variety of analytical approaches have been developed for the study of quantum spin systems in two dimensions, the notable ones being spin-waves, slave boson/fermion parton constructions, and for lattices with one-to-one local…
Ground state and low-energy excitations of the quasi-one-dimensional antiferromagnet CuSe$_2$O$_5$ were experimentally studied using bulk magnetization, neutron diffraction, muon spin relaxation and antiferromagnetic resonance measurements.…
We investigate the antiferromagnetic (AF) order in the d-wave superconducting (SC) state at high magnetic fields. A two-dimensional model with on-site repulsion U, inter-site attractive interaction V and antiferromagnetic exchange…
Motivated by the recent discoveries of ferromagnetic and non-centrosymmetric superconductors, we present a mean-field theory for a superconductor that \textit{both} lacks inversion symmetry and displays ferromagnetism, a scenario which is…
We analyze whether and how the neutron resonance mode in unconventional superconductors is affected by higher order corrections in the coupling between spin excitations and fermionic quasiparticles and find that in general such corrections…
We investigate the competition between spin-supersolidity and phase separation in a frustrated spin-half model of weakly coupled dimers. We start by considering systems of hard-core bosons on the square lattice, onto which the low-energy…
We compute transport and thermodynamic properties of a two-band spin-fermion model describing itinerant fermions in two dimensions interacting via $Z_2$ antiferromagnetic quantum critical fluctuations by means of a sign-problem-free quantum…
Early studies proposed a connection between cuprate superconductivity and fractionalized spin liquid states. But the low temperature phase diagram is dominated by states without fractionalization, with a competition between…
The influence of antiferromagnetic order on the superconductivity in the non-centrosymmetric heavy fermion compound CePt$_3$Si and related materials is discussed. Based on our RPA analysis for the extended Hubbard model two phases could be…
This is a review of the properties of 2d quantum quasiperiodic antiferromagnets as reported in studies that have been carried out in the last decade. Many results have been obtained for perfectly ordered as well as for disordered two…
We show that a Chern-Simons term for a gauge field describing a fluctuation of spins is induced by integrating out hole fields in the presence of spin-orbit coupling which originates from a buckling of the CuO$_2$ plane. Through the…