resumo
Ferroelectric materials exhibit spontaneous polarization that can be switched by electric field. Beyond traditional applications as nonvolatile capacitive elements, the interplay between polarization and electronic transport in ferroelectric thin films has enabled a path to neuromorphic device applications involving resistive switching. A fundamental challenge, however, is that finite electronic conductivity may introduce considerable power dissipation and perhaps destabilize ferroelectricity itself. Here, tunable microwave frequency electronic response of domain walls injected into ferroelectric lead zirconate titanate (PbZr0.2Ti0.8O3) on the level of a single nanodomain is revealed. Tunable microwave response is detected through first-order reversal curve spectroscopy combined with scanning microwave impedance microscopy measurements taken near 3 GHz. Contributions of film interfaces to the measured AC conduction through subtractive milling, where the film exhibited improved conduction properties after removal of surface layers, are investigated. Using statistical analysis and finite element modeling, we inferred that the mechanism of tunable microwave conductance is the variable area of the domain wall in the switching volume. These observations open the possibilities for ferroelectric memristors or volatile resistive switches, localized to several tens of nanometers and operating according to well-defined dynamics under an applied field.
palavras-chave
DOMAIN-WALLS; POLARIZATION
categoria
Science & Technology - Other Topics; Materials Science; Physics
autores
Burns, SR; Tselev, A; Ievlev, AV; Agar, JC; Martin, LW; Kalinin, SV; Sando, D; Maksymovych, P
nossos autores
Alexander Tselev
Investigador Principalagradecimentos
Experiments and modelling have been carried out at the Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, which is a DOE Office of Science User Facility. This research was supported in part by the Australian Research Council Centre of Excellence in Future Low-Energy Electronics Technologies (Project No. CE170100039) and funded by the Australian Government. This project was supported in part by an appointment to the Science Education and Workforce Development Programs at Oak Ridge National Laboratory, administered by ORISE through the U.S. Department of Energy Oak Ridge Institute for Science and Education. S.R.B. acknowledges funding in part from the UNSW Science Ph.D. Writing Scholarship and current funding from the Canada First Research Excellence Fund. In part (A.T.), this work was developed within the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020 and UIDP/50011/2020, financed by national funds through the FCT/MEC and when appropriate cofinanced by FEDER under the PT2020 Partnership Agreement. J.C.A. acknowledges primary support from the National Science Foundation under grant TRIPODS + X: RES-1839234. L.W.M. acknowledges support of the National Science Foundation under Grant No. DMR-1708615. The authors would like to thank Liam Collins and Rama Vasudevan for assistance with the experimental set-up.