title: Multicritical point in a diluted bilayer Heisenberg quantum antiferromagnet.
abstract: The S=1/2 Heisenberg bilayer antiferromagnet with randomly removed interlayer dimers is studied using quantum Monte Carlo simulations. A zero-temperature multicritical point (p(*),g(*)) at the classical percolation density p=p(*) and interlayer coupling g(*) approximately equal 0.16 is demonstrated. The quantum critical exponents of the percolating cluster are determined using finite-size scaling. It is argued that the associated finite-temperature quantum critical regime extends to zero interlayer coupling and could be relevant for antiferromagnetic cuprates doped with nonmagnetic impurities.
authors.affiliation: Department of Physics, Abo Akademi University, Porthansgatan 3, FIN-20500 Turku, Finland.
authors.forename: Anders W
authors.initials: AW
authors.lastname: Sandvik