title: Direct evidence for an intrinsic square vortex lattice in the overdoped high- T(c) superconductor La(1.83)Sr(0.17)CuO(4+delta).
abstract: We report here the first direct observations of a well ordered vortex lattice in the bulk of a La(2-x)Sr(x)CuO(4+delta) single crystal (slightly overdoped, x = 0.17). Our small angle neutron scattering investigation of the mixed phase reveals a crossover from triangular to square coordination with increasing magnetic field. The existence of an intrinsic square vortex lattice has never been observed in high-temperature superconductors and is indicative of the coupling of the vortex lattice to a source of anisotropy, such as those provided by a d-wave order parameter or the presence of stripes.
authors.affiliation: Laboratory for Neutron Scattering, ETH Zurich and PSI Villigen, CH-5232 Villigen PSI, Switzerland.
authors.forename: R
authors.initials: R
authors.lastname: Gilardi
authors.forename: J
authors.initials: J
authors.lastname: Mesot
authors.forename: A
authors.initials: A
authors.lastname: Drew
authors.forename: U
authors.initials: U
authors.lastname: Divakar
authors.forename: S L
authors.initials: SL
authors.lastname: Lee
authors.forename: E M
authors.initials: EM
authors.lastname: Forgan
authors.forename: O
authors.initials: O
authors.lastname: Zaharko
authors.forename: K
authors.initials: K
authors.lastname: Conder
authors.forename: V K
authors.initials: VK
authors.lastname: Aswal
authors.forename: C D
authors.initials: CD
authors.lastname: Dewhurst
authors.forename: R
authors.initials: R
authors.lastname: Cubitt
authors.forename: N
authors.initials: N
authors.lastname: Momono
authors.forename: M
authors.initials: M
authors.lastname: Oda