Magnetization dynamics and frustration in the multiferroic double perovskite Lu2MnCoO6

Zapf, V.S.; Ueland, B.G.; Laver, M.; Lonsky, M.; Pohlit, M.; Muller, J.; Lancaster, T.; Moller, J.S.; Blundell, S.J.; Singleton, J.; Mira, J.; Yanez-Vilar, S.; Senarıs-Rodrıguez, M.A.

Abstract

We investigate the magnetic ordering and the magnetization dynamics (from kHz to THz time scales) of the double perovskite Lu2MnCoO6 using elastic neutron diffraction, muon spin relaxation, and micro-Hall magnetization measurements. This compound is known to be a type II multiferroic with the interesting feature that a ferromagneticlike magnetization hysteresis loop couples to an equally hysteretic electric polarization in the bulk of the material despite a zero-field magnetic ordering of the type ↑↑↓↓ along Co-Mn spin chains. Here we explore the unusual dynamics of this compound and find extremely strong fluctuations, consistent with the axial next-nearest-neighbor Ising (ANNNI) model for frustrated spin chains. We identify three temperature scales in Lu2MnCoO6 corresponding to the onset of highly fluctuating long-range order below TN=50±3 K identified from neutron scattering, the onset of magnetic and electric hysteresis, with change in kHz magnetic and electric dynamics below a 30 K temperature scale, and partial freezing of ∼MHz spin fluctuations in the muon spin relaxation data below 12±3 K. Our results provide a framework for understanding the multiferroic behavior of this compound and its hysteresis and dynamics.

Citation

Zapf, V., Ueland, B., Laver, M., Lonsky, M., Pohlit, M., Muller, J., …Senarıs-Rodrıguez, M. (2016). Magnetization dynamics and frustration in the multiferroic double perovskite Lu2MnCoO6. Physical Review B, 93(13), Article 134431. https://doi.org/10.1103/physrevb.93.134431

• Journal Article Type: Article
• Acceptance Date: Apr 11, 2016
• Online Publication Date: Apr 29, 2016
• Publication Date: Apr 29, 2016
• Deposit Date: May 12, 2016
• Publicly Available Date: May 17, 2016
• Journal: Physical Review B
• Print ISSN: 2469-9950
• Electronic ISSN: 2469-9969
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 93
• Issue: 13
• Article Number: 134431
• DOI: https://doi.org/10.1103/physrevb.93.134431
• Public URL: https://durham-repository.worktribe.com/output/1384466
• Related Public URLs: http://arxiv.org/abs/1409.5072