Thermally assisted interlayer magnetic coupling through Ba0.05Sr0.95TiO3 barriers"

SANTIAGO CARREIRA, LUIS AVILES FELIX, MARTÍN SIRENA, GABRIELA ALEJANDRO, LAURA B. STEREN

APPLIED PHYSICS LETTERS

AMER INST PHYSICS

Lugar: New York; Año: 2016 vol. 109 p. 62402 - 62406

0003-6951

We report on the interlayerexchange coupling across insulating barriers observed on Ni80Fe20/Ba0.05Sr0.05TiO3 La0.66Sr0.33MnO3 trilayers. The coupling mechanism has been analyzed in terms of the barrierthickness, samples´substrate and temperature.We examined the effect of MgO and SrTiO3 (001) single-crystalline substrates on the magnetic coupling and also on themagnetic anisotropies of the samples in order to get a deeper understanding ofthe magnetism of the,structures. Wemeasured a weak coupling mediated by spin-dependent tunneling phenomena whosesign and strength depend on barrier thickness and substrate. Anantiferromagnetic exchange prevails for most of the samples and smoothlyincreases with the barrier thicknesses as a consequence of the screeningeffects of the BST. The couplingmonotonically increases with temperature in all the samples and this behaviouris attributed to thermally assisted mechanisms. The magnetic anisotropy of bothmagnetic components has a cubic symmetrythat in the case of permalloy is added to a small uniaxial component.