Full Electroresistance Modulation in a Mixed-Phase Metallic Alloy

Z. Q. Liu, L. Li, Z. Gai, J. D. Clarkson, S. L. Hsu, A. T. Wong, L. S. Fan, M.-W. Lin, C. M. Rouleau, T. Z. Ward, H. N. Lee, A. S. Sefat, H. M. Christen, and R. Ramesh

Phys. Rev. Lett. 116, 097203 – Published 3 March 2016

Abstract

We report a giant, $\sim 22 %$ , electroresistance modulation for a metallic alloy above room temperature. It is achieved by a small electric field of $2 kV / cm$ via piezoelectric strain-mediated magnetoelectric coupling and the resulting magnetic phase transition in epitaxial $FeRh / {BaTiO}_{3}$ heterostructures. This work presents detailed experimental evidence for an isothermal magnetic phase transition driven by tetragonality modulation in FeRh thin films, which is in contrast to the large volume expansion in the conventional temperature-driven magnetic phase transition in FeRh. Moreover, all the experimental results in this work illustrate FeRh as a mixed-phase model system well similar to phase-separated colossal magnetoresistance systems with phase instability therein.

Received 19 August 2015

DOI:https://doi.org/10.1103/PhysRevLett.116.097203

Physics Subject Headings (PhySH)

Electrical properties Magnetism Magnetoelectric effect

Alloys Thin films

Condensed Matter, Materials & Applied Physics

Authors & Affiliations

Z. Q. Liu^1,2,*, L. Li³, Z. Gai¹, J. D. Clarkson², S. L. Hsu², A. T. Wong^3,4, L. S. Fan³, M.-W. Lin¹, C. M. Rouleau¹, T. Z. Ward³, H. N. Lee³, A. S. Sefat³, H. M. Christen^1,†, and R. Ramesh^2,5,6,7,‡

¹Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
²Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA
³Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
⁴Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996, USA
⁵Department of Physics, University of California, Berkeley, California 94720, USA
⁶Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
⁷Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA