6 papers
Optical Absorption of CuO antiferromagnetic chains at finite temperatures
Eduardo Gagliano, Fabian Lema, Silvia Bacci +2
We use a high-statistic quantum Monte Carlo and Maximum Entropy regularization method to compute the dynamical energy correlation function (DECF) of the one-dimensional (1D) $S=1/2…
Spectral function and quasiparticle weight in the generalized t-J model
F. Lema, A. A. Aligia
We extend to the spectral function an approach which allowed us to calculate the quasiparticle weight for destruction of a real electron Z_c sigma (k) (in contrast to that of creat…
Charge and spin excitations of insulating lamellar copper oxides
F. Lema, J. Eroles, C. D. Batista +1
A consistent description of low-energy charge and spin responses of the insulating Sr_2CuO_2Cl_2 lamellar system is found in the framework of a one-band Hubbard model which besides…
Quasiparticle photoemission intensity in doped two-dimensional quantum antiferromagnets
F. Lema, A. A. Aligia
Using the self-consistent Born approximation, and the corresponding wave function of the magnetic polaron, we calculate the quasiparticle weight corresponding to destruction of a r…
Excitons in insulating cuprates
M. E. Simón, A. A. Aligia, C. D. Batista +2
We study the electronic excitations near the charge-transfer gap in insulating CuO planes, starting from a six-band model which includes and orbitals and Cu-O…
Superconductivity from correlated hopping
C. D. Batista, F. Lema, A. A. Aligia
We consider a chain described by a next-nearest-neighbor hopping combined with a nearest-neighbor spin flip. In two dimensions this three-body term arises from a mapping of the thr…