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arXiv · 1806.04775

Emergent c-axis magnetic helix in manganite-nickelate superlattices

G. Fabbris·N. Jaouen·D. Meyers·J. Feng·J. D. Hoffman·R. Sutarto·S. G. Chiuzbaian·A. Bhattacharya·M. P. M. Dean
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Abstract

The nature of the magnetic order in (La2/3Sr1/3MnO3)9/(LaNiO3)3 superlattices is investigated using x-ray resonant magnetic reflectometry. We observe a new c-axis magnetic helix state in the (LaNiO3)3 layers that had never been reported in nickelates, and which mediates the ~130deg magnetic coupling between the ferromagnetic (La2/3Sr1/3MnO3)9 layers, illustrating the power of x-rays for discovering the magnetic state of complex oxide interfaces. Resonant inelastic x-ray scattering and x-ray absorption spectroscopy show that Ni-O ligand hole states from bulk LaNiO3 are mostly filled due to interfacial electron transfer from Mn, driving the Ni orbitals closer to an atomic-like 3d8 configuration. We discuss the constraints imposed by this electronic configuration to the microscopic origin of the observed magnetic structure. The presence of a magnetic helix in (La2/3Sr1/3MnO3)9/(LaNiO3)3 is crucial for modeling the potential spintronic functionality of this system and may be important for designing emergent magnetism in novel devices in general.

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G. Fabbris, N. Jaouen, D. Meyers, J. Feng, J. D. Hoffman, R. Sutarto, S. G. Chiuzbaian, A. Bhattacharya, M. P. M. Dean. 2018-06-12. Emergent c-axis magnetic helix in manganite-nickelate superlattices. https://doi.org/10.1103/physrevb.98.180401

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