4 papers
Magnetic and orbital ordering of RuO2 planes in RuSr2(Eu,Gd)Cu2O8
A. A. Aligia, M. A. Gusmao
We start from an effective Hamiltonian for Ru ions in a square lattice, which includes the on-site interactions between t_2g orbitals derived from Coulomb repulsion, and a tetragon…
Disorder effects at low temperatures in La_{0.7-x}Y_{x}Ca_{0.3}MnO_{3} manganites
M. A. Gusmao, L. Ghivelder, R. S. Freitas +4
With the aim of probing the effect of magnetic disorder in the low-temperature excitations of manganites, specific-heat measurements were performed in zero field, and in magnetic f…
Band-filling effects on the Kondo-lattice properties
B. Coqblin, C. Lacroix, M. A. Gusmão +1
We present theoretical results for a Kondo-lattice model with spin-1/2 localized moments, including both the intrasite Kondo coupling and an intersite antiferromagnetic exchange in…
Superconductivity in the Kondo lattice: a mean-field approach
M. A. Gusmao, A. A. Aligia
We calculate the superconducting critical temperature T_c and the Kondo temperature T_K of the Kondo lattice, decoupling the Kondo exchange interaction in the unrestricted Hartree-…