Related papers: The Phase Separation Scenario for Manganese Oxides
A largely descriptive survey is given of the ordered phases of doped antiferromagnets, and of the long wavelength properties that can be derived from an order-parameter theory. In particular, we show that the competition between the…
It is shown that the double exchange Hamiltonian, with weak antiferromagnetic interactions, has a rich variety of first order transitions between phases with different electronic densities and/or magnetizations. For band fillings in the…
Spatially uniform electric fields have been used to induce instabilities in liquids and polymers, and to orient and deform ordered phases of block-copolymers. Here we discuss the demixing phase transition occurring in liquid mixtures when…
We discuss our very interesting experimental observation that the low-temperature two-phase coexistence in half-doped manganites is multi-valued (at any field) in that we can tune the coexisting antiferromagnetic-insulating(AF-I) and the…
We investigated slow relaxations of the magnetostriction and residual magnetostriction of the phase-separated system (Eu$_{1-x}$Gd$_{x}$)$_{0.6}$Sr$_{0.4}$MnO$_3$, in which the metamagnetic transition from a paramagnetic insulating state to…
The paramagnetic phase diagram of the Hubbard model with nearest-neighbor (NN) and next-nearest-neighbor (NNN) hopping on the Bethe lattice is computed at half-filling and in the weakly doped regime using the self-energy functional approach…
We show that the main features of the cuprates superconductors phase diagram can be derived considering the disorder as a key property of these materials. Our basic point is that the high pseudogap line is an onset of phase separation which…
We have studied the magnetic relaxation properties of the phase-separated manganite compound La0.250Pr0.375Ca0.375MnO3 . A series of polycrystalline samples was prepared with different sintering temperatures, resulting in a continuous…
The interplay of the electron-phonon interaction and of the double and super exchange magnetic effects is analyzed in the $La_{1-x}Ca_xMnO_3$ perovskites with $0<x<0.5$. By using an analytical variational scheme that allows to treat the…
Spin, charge, and orbital structures in models for doped manganites are studied by a combination of analytic mean-field and numerical relaxation techniques. At realistic values for the electron-phonon and antiferromagnetic $t_{2g}$ spin…
We have studied the low-frequency dielectric properties of the phase-separated manganite Pr0.7Ca0.3MnO3 as a function of applied magnetic field in the low temperature phase-separated state. The dielectric constant is strongly field…
Charge order pervades the phase diagrams of quantum materials where it competes with superconducting and magnetic phases, hosts electronic phase transitions and topological defects, and couples to the lattice generating intricate structural…
We study the phases of correlated charge-density waves that form at a high magnetic field in two parallel graphene flakes separated by a thin insulator. The predicted phases include the square and hexagonal charge-density-wave bubbles, and…
For intermediate Coulomb energy to Fermi energy ratios $r_s$, spinless fermions in a two-dimensional random potential form a new quantum phase, different from the Fermi glass (weakly interacting Anderson localized states) and the Wigner…
The physics of manganites appears to be dominated by phase competition among ferromagnetic metallic and charge-ordered antiferromagnetic insulating states. Previous investigations (Burgy {\it et al.}, Phys. Rev. Lett. {\bf 87}, 277202…
The phase diagram of Pr0.65(CaySr1-y)0.35MnO3, 0.6 <= y <= 0.8, has been determined by neutron diffraction, magnetization and electrical conductivity measurements in order to investigate the nature of the transition between ferromagnetic…
It was discovered in La1-xSrxMnO3(x~1/8) that a field induced phase transition occurs from a ferromagnetic metal(FM) phase to a ferromagnetic insulator (FI) phase. The magnetization shows a sharp jump at the transition field accompanying…
A model of localized classical electrons coupled to lattice degrees of freedom and, via the Coulomb interaction, to each other, has been studied to gain insight into the charge and orbital ordering observed in lightly doped manganese…
Confinement effects on the phase transitions in antiferromagnets are studied as a function of the surface coupling v and the surface field h for bcc(110) films. Unusual topologies for the phase diagram are attained for particular…
Stripe order is a prominent feature in the phase diagram of the high-temperature cuprate superconductors. It has been confirmed as the lowest-energy state of the two-dimensional Fermi Hubbard model in certain parameter regimes. Upon…