title: Upper limit to magnetism in LaAlO3/SrTiO3 heterostructures.
abstract: Using polarized neutron reflectometry we measured the neutron spin-dependent reflectivity from four LaAlO(3)/SrTiO(3) superlattices. Our results imply that the upper limit for the magnetization averaged over the lateral dimensions of the sample induced by an 11 T magnetic field at 1.7 K is less than 2 G. SQUID magnetometry of the neutron superlattice samples sporadically finds an enhanced moment, possibly due to experimental artifacts. These observations set important restrictions on theories which imply a strongly enhanced magnetism at the interface between LaAlO(3) and SrTiO(3).
authors.affiliation: Los Alamos National Laboratory, New Mexico 87545, USA.
authors.forename: M R
authors.initials: MR
authors.lastname: Fitzsimmons
authors.forename: N W
authors.initials: NW
authors.lastname: Hengartner
authors.forename: S
authors.initials: S
authors.lastname: Singh
authors.forename: M
authors.initials: M
authors.lastname: Zhernenkov
authors.forename: F Y
authors.initials: FY
authors.lastname: Bruno
authors.forename: J
authors.initials: J
authors.lastname: Santamaria
authors.forename: A
authors.initials: A
authors.lastname: Brinkman
authors.forename: M
authors.initials: M
authors.lastname: Huijben
authors.forename: H J A
authors.initials: HJ
authors.lastname: Molegraaf
authors.forename: J
authors.initials: J
authors.lastname: de la Venta
authors.forename: Ivan K
authors.initials: IK
authors.lastname: Schuller