title: Quantum magnetism in the paratacamite family: towards an ideal kagomé lattice.
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.
authors.affiliation: Laboratoire de Physique des Solides, UMR CNRS 8502, Université Paris-Sud, 91405 Orsay, France.
authors.forename: P
authors.initials: P
authors.lastname: Mendels
authors.forename: F
authors.initials: F
authors.lastname: Bert
authors.forename: M A
authors.initials: MA
authors.lastname: de Vries
authors.forename: A
authors.initials: A
authors.lastname: Olariu
authors.forename: A
authors.initials: A
authors.lastname: Harrison
authors.forename: F
authors.initials: F
authors.lastname: Duc
authors.forename: J C
authors.initials: JC
authors.lastname: Trombe
authors.forename: J S
authors.initials: JS
authors.lastname: Lord
authors.forename: A
authors.initials: A
authors.lastname: Amato
authors.forename: C
authors.initials: C
authors.lastname: Baines