Quantum magnetism in the paratacamite family: towards an ideal kagomé lattice.

Authors :: Mendels P
Bert F
de Vries MA
Olariu A
Harrison A
Duc F
Trombe JC
Lord JS
Amato A
Baines C
Source :: Physical review letters [Phys Rev Lett] 2007 Feb 16; Vol. 98 (7), pp. 077204. Date of Electronic Publication: 2007 Feb 13.
Publication Year :: 2007
Abstract: We report muon spin rotation measurements on the S=1/2 (Cu2+) paratacamite ZnxCu4-x(OH)6Cl2 family. Despite a Weiss temperature of approximately -300 K, the x=1 compound is found to have no transition to a magnetic frozen state down to 50 mK as theoretically expected for the kagomé Heisenberg antiferromagnet. We find that the limit between a dynamical and a partly frozen ground state occurs around x=0.5. For x=1, we discuss the relevance to a singlet picture.