Spin excitations and exchange couplings in the cuprate antiferromagnet La2CuO4
01 March 2000
The spin excitations in La2CuO4, a two-dimensional spin-1/2 Heisenberg antiferromagnet and parent compound of high-T-c, superconductors, have been measured throughout the Brillouin zone using high-resolution inelastic neutron scattering. The observed dispersion relations show evidence for substantial second- or third-nearest-neighbour exchange couplings in addition to the strong first nearest-neighbour antiferromagnetic exchange. (C) 2000 Elsevier Science B.V. All rights reserved.