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arXiv · 1601.07360

The effect of interface roughness on exchange bias in La0.7Sr0.3MnO3 - BiFeO3 heterostructures

Mehran Vafaee·Simone Finizio·Hakan Deniz·Dietrich Hesse·Hartmut Zabel·Gerhard Jakob·Mathias Kläui
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Abstract

We characterized the interfaces of heterostructures with different stack sequences of La0.7Sr0.3MnO3/BiFeO3 (LSMO/BFO) and BFO/LSMO using TEM revealing sharp and rough interfaces, respectively. Magnetometry and magnetoresistance measurements do not show a detectable exchange bias coupling for the multistack with sharp interface. Instead, the heterostructures with rough and chemically intermixed interfaces exhibit a sizable exchange bias coupling. Furthermore, we find a temperature-dependent irreversible magnetization behavior and an exponential decay of coercive and exchange bias field with temperature suggesting a possible spin-glass-like state at the interface of both stacks.

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Mehran Vafaee, Simone Finizio, Hakan Deniz, Dietrich Hesse, Hartmut Zabel, Gerhard Jakob, Mathias Kläui. 2016-01-27. The effect of interface roughness on exchange bias in La0.7Sr0.3MnO3 - BiFeO3 heterostructures. https://doi.org/10.1063/1.4941795

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