Experimental Evidence of a Haldane Gap in an S = 2 Quasi-Linear-Chain Antiferromagnet
Abstract
The magnetic susceptibility of the S = 2 quasi-linear-chain Heisenberg antiferromagnet (2,2'-bipyridine)trichloromanganese(III) has been measured from 1.8 to 300 K with the magnetic field H parallel and perpendicular to the chains. The analyzed data yield g~2 and J~35 K. The magnetization M has been studied at 30 mK and 1.4 K in H up to 16 T. No evidence of long-range order is observed. Depending on crystal orientation, M~0 at 30 mK until a critical field is achieved ( Hc|| = 1.2+/-0.2 T and Hc⊥ = 1.8+/-0.2 T), where M increases continuously as H is increased. These results are interpreted as evidence of a Haldane gap.
- Publication:
-
Physical Review Letters
- Pub Date:
- August 1996
- DOI:
- 10.1103/PhysRevLett.77.1616
- arXiv:
- arXiv:cond-mat/9707132
- Bibcode:
- 1996PhRvL..77.1616G
- Keywords:
-
- Condensed Matter - Strongly Correlated Electrons
- E-Print:
- 11 pages, 4 figures