Scanning SQUID Imaging of Noncollinear Antiferromagnetic Domains in EuTiO<sub>3</sub> film
ORAL
Abstract
Magnetic and ferroelectric instabilities in antiferromagnet EuTiO3 provide a rare platform to study multiferroic quantum critical phenomena and strong magnetoelectric couplings. Despite extensive experimental efforts, the magnetic structure remains without consensus. Neutron diffraction analysis is inconclusive due to large neutron absorption. Uncertainty arises in X-ray magnetic scattering due to the presence of magnetic domains. Here, we report temperature dependent local magnetic measurements of a thin film of EuTiO3 deposited on SrTiO3 using a scanning superconducting quantum interference device (SQUID) microscope. Magnetic flux and susceptibility images reveal the formation of weakly ferromagnetic domains below the film’s Néel temperature, indicative of a noncollinear or canted antiferromagnetic state. Noncollinear magnetic ordering lowers the magnetic symmetry of EuTiO3, which may influence current interpretations of magnetoelectric and magnetoelastic effects and predictions of quantum critical behavior.
*We gratefully acknowledge the Air Force Research Laboratory, Materials and Manufacturing Directorate (AFRL/RXMS) for support via Contract No. FA8650–21–C5711. This work was also supported by NSF Award 2233149, UCONN Quantum Region Partnership Investment, and Quantum SEED Awards. Distribution A. Approved for public release: distribution unlimited. (AFRL-2024-5192) Date Approved 09-23-2024
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Publication: J.Bedard, et al, Noncollinear Antiferromagnetism and Emergent Dynamic Order in EuTiO3 Film, In Preparation (2024).
Presenters
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Joshua Bedard
- University of Connecticut