DIRECT CALCULATION OF SPIN STIFFNESS FOR SPIN-1 2 HEISENBERG MODELS/

Authors
BONCA J RODRIGUEZ JP FERRER J BEDELL KS
Citation
J. Bonca et al., DIRECT CALCULATION OF SPIN STIFFNESS FOR SPIN-1 2 HEISENBERG MODELS/, Physical review. B, Condensed matter, 50(5), 1994, pp. 3415-3418
Citations number
17
Categorie Soggetti
Physics, Condensed Matter
Journal title
Physical review. B, Condensed matter → ACNP
ISSN journal
01631829
Volume
50
Issue
5
Year of publication
1994
Pages
3415 - 3418
Database
ISI
SICI code
0163-1829(1994)50:5<3415:DCOSSF>2.0.ZU;2-6
Abstract
The spin stiffness of frustrated spin-1/2 Heisenberg models in one and two dimensions is computed by exact diagonalizations on small cluster s that implement spin-dependent twisted boundary conditions. Finite-si ze extrapolation to the thermodynamic limit yields a value of 0.14 +/- 0.01 for the spin stiffness of the unfrustrated planar antiferromagne t. We also present a general discussion of the linear-response theory for spin twists, which ultimately leads to the moment sum rule.