title: Magnetic-field effects on the size of vortices below the surface of NbSe2 detected using low energy beta-NMR.
abstract: A low energy radioactive beam of polarized 8Li has been used to observe the vortex lattice near the surface of superconducting NbSe2. The inhomogeneous magnetic-field distribution associated with the vortex lattice was measured using depth-resolved beta-detected NMR. Below Tc, one observes the characteristic line shape for a triangular vortex lattice which depends on the magnetic penetration depth and vortex core radius. The size of the vortex core varies strongly with the magnetic field. In particular, in a low field of 10.8 mT, the core radius is much larger than the coherence length. The possible origin of these giant vortices is discussed.
authors.affiliation: TRIUMF, 4004 Wesbrook Mall, Vancouver, BC, Canada.
authors.forename: Z
authors.initials: Z
authors.lastname: Salman
authors.forename: D
authors.initials: D
authors.lastname: Wang
authors.forename: K H
authors.initials: KH
authors.lastname: Chow
authors.forename: M D
authors.initials: MD
authors.lastname: Hossain
authors.forename: S R
authors.initials: SR
authors.lastname: Kreitzman
authors.forename: T A
authors.initials: TA
authors.lastname: Keeler
authors.forename: C D P
authors.initials: CD
authors.lastname: Levy
authors.forename: W A
authors.initials: WA
authors.lastname: MacFarlane
authors.forename: R I
authors.initials: RI
authors.lastname: Miller
authors.forename: G D
authors.initials: GD
authors.lastname: Morris
authors.forename: T J
authors.initials: TJ
authors.lastname: Parolin
authors.forename: H
authors.initials: H
authors.lastname: Saadaoui
authors.forename: M
authors.initials: M
authors.lastname: Smadella
authors.forename: R F
authors.initials: RF
authors.lastname: Kiefl