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Spin waves in La_2CuO_4: band structure and correlation effects

N. M. R. Peres·M. A. N. Araujo
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Abstract

We calculate the antiferromagnetic spin wave dispersion in the half-filled (electronic density n=1) Hubbard model for a two-dimensional square lattice, using the random phase approximation (RPA) in a broken symmetry (spin density wave) ground state. Our results for the spin wave dispersion, ω(\vec q), are compared with high-resolution inelastic neutron scattering performed on La_2CuO$_4. The effects of different band structures and different values of the on-site Coulomb interaction on the spin wave spectrum is studied. Particular attention is put on the high energy dispersion values ω(π/2,π/2) and ω(0,π).

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N. M. R. Peres, M. A. N. Araujo. 2003-03-20. Spin waves in La_2CuO_4: band structure and correlation effects. https://doi.org/10.1002/pssb.200301719

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