We consider the square lattice Heisenberg antiferromagnet with plaquette ring exchange (J□) to investigate the spin dynamics in La 2CuO4. The values for the in-plane exchange parameters, J=151.9 meV and J□=0.24 J, are obtained consistently by an accurate fit to the experimentally observed spin-wave dispersion. In a parameter-free calculation for the Raman light scattering intensity we find that the inclusion of ring exchange in the dispersion and the magnon-magnon interaction vertex leads to a 2-magnon peak position in B1g geometry which agrees perfectly with the experimental value.
|Number of pages||2|
|Journal||Physica C: Superconductivity and its Applications|
|Publication status||Published - Aug 2004|
|Event||Proceedings of the International Conference on Materials - Rio de Janeiro, Brazil|
Duration: 25 May 2003 → 30 May 2003
- Magnetic Raman scattering
- Spin waves