Large resistivity modulation in mixed-phase metallic systems

Yeonbae Lee; Z Q Liu; J T Heron; J D Clarkson; J Hong; C Ko; M D Biegalski; U Aschauer; S L Hsu; M E Nowakowski; J Wu; H M Christen; S Salahuddin; J B Bokor; N A Spaldin; D G Schlom; R Ramesh

doi:10.1038/ncomms6959

Large resistivity modulation in mixed-phase metallic systems

Nat Commun. 2015 Jan 7:6:5959. doi: 10.1038/ncomms6959.

Authors

Yeonbae Lee¹, Z Q Liu², J T Heron³, J D Clarkson¹, J Hong⁴, C Ko¹, M D Biegalski², U Aschauer⁵, S L Hsu¹, M E Nowakowski⁴, J Wu⁶, H M Christen², S Salahuddin⁴, J B Bokor⁷, N A Spaldin⁵, D G Schlom⁸, R Ramesh⁹

Affiliations

¹ Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA.
² Oak Ridge National Laboratory, Center for Nanophase Materials Sciences, Oak Ridge, Tennessee 37831, USA.
³ Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA.
⁴ Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, California 94720, USA.
⁵ Materials Theory, ETH Zurich, Wolfgang-Pauli-Strasse 27, CH-8093 Zürich, Switzerland.
⁶ 1] Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA [2] Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
⁷ 1] Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, California 94720, USA [2] Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
⁸ 1] Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA [2] Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853, USA.
⁹ 1] Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA [2] Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA [3] Department of Physics, University of California, Berkeley, California 94720, USA [4] Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.

PMID: 25564764
DOI: 10.1038/ncomms6959

Abstract

In numerous systems, giant physical responses have been discovered when two phases coexist; for example, near a phase transition. An intermetallic FeRh system undergoes a first-order antiferromagnetic to ferromagnetic transition above room temperature and shows two-phase coexistence near the transition. Here we have investigated the effect of an electric field to FeRh/PMN-PT heterostructures and report 8% change in the electrical resistivity of FeRh films. Such a 'giant' electroresistance (GER) response is striking in metallic systems, in which external electric fields are screened, and thus only weakly influence the carrier concentrations and mobilities. We show that our FeRh films comprise coexisting ferromagnetic and antiferromagnetic phases with different resistivities and the origin of the GER effect is the strain-mediated change in their relative proportions. The observed behaviour is reminiscent of colossal magnetoresistance in perovskite manganites and illustrates the role of mixed-phase coexistence in achieving large changes in physical properties with low-energy external perturbation.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.