Quantum magnetic interactions in <B>S</B> = 1/2 KCuCl3
Abstract
KCuCl3 is an S = 1/2 magnetic insulator with a singlet ground state and a finite spin excitation gap. Above the gap, dispersive triplet excitation modes propagate in the whole reciprocal space. From single-crystal inelastic neutron investigations the three-dimensional coupling scheme is rationalized in the framework of a dimer Heisenberg model, and related to the structural features of KCuCl3. The experimental and theoretical characterization presented completes earlier works on the compound under investigation, providing also higher-order expressions for the singlet-triplet dispersion relation. The latter may also be of relevance for the parent quantum systems TlCuCl3 and NH4CuCl3, albeit at different coupling ratios with respect to KCuCl3.
- Publication:
-
Journal of Physics Condensed Matter
- Pub Date:
- June 2000
- DOI:
- 10.1088/0953-8984/12/25/310
- Bibcode:
- 2000JPCM...12.5463C