Emergent Ferromagnetism in (111)-oriented CaRuO3/CaMnO3 superlattices

ORAL

Abstract

Emergent ferromagnetism has been observed at the interface of CaRuO3 (CRO), a paramagnetic metal, and CaMnO3 (CMO), an antiferromagnetic insulator. The leakage of itinerant CRO electrons into the CMO results in a double exchange interaction among interfacial Mn. Since CMO is a G-type antiferromagnet, films grown in (111) direction should have fully uncompensated surfaces and higher interfacial moments than compensated (001) surfaces. We demonstrate the synthesis and characterization of (111) CRO/CMO superlattices with 3 layers of CRO and 3-19 layers of CMO. To grow smooth (111) superlattices, we developed an interval pulsed laser deposition process. SQUID magnetometry measurements indicate larger interfacial Mn moments in our (111) superlattices compared to (001) superlattices. Coercive fields of the superlattice are similar, regardless of CMO thickness, and with increasing CMO thickness, the exchange bias field in the magnetization loops increases. Since CMO and CRO are isovalent, CRO/CMO systems do not exhibit a polarity mismatch across the interface, providing a model system to explore emergent ferromagnetism.

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Presenters

  • Margaret Kane

    Material Science and Engineering, Stanford University

Authors

  • Margaret Kane

    Material Science and Engineering, Stanford University

  • Charles Flint

    Material Science and Engineering, Stanford University

  • Arturas Vailionis

    Geballe Laboratory for Advanced Materials, Stanford University

  • Alexander Grutter

    National Institute of Standards and Technology, NIST, NIST Center for Neutron Research, NIST Gaithersburg, Neutron-Condensed Matter Science Group, NIST, NIST Center for Neutron Research

  • Yuri Suzuki

    Stanford University, Department of Applied Physics, Stanford University, Applied Physics, Stanford University, Geballe Laboratory for Advanced Materials, Stanford University