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Title: Controlled manipulation of oxygen vacancies using nanoscale flexoelectricity

Abstract

Oxygen vacancies, especially their distribution, are directly coupled to the electromagnetic properties of oxides and related emergent functionalities that have implications for device applications. Here using a homoepitaxial strontium titanate thin film, we demonstrate a controlled manipulation of the oxygen vacancy distribution using the mechanical force from a scanning probe microscope tip. By combining Kelvin probe force microscopy imaging and phase-field simulations, we show that oxygen vacancies can move under a stress-gradient-induced depolarisation field. When tailored, this nanoscale flexoelectric effect enables a controlled spatial modulation. In motion, the scanning probe tip thereby deterministically reconfigures the spatial distribution of vacancies. Finally, the ability to locally manipulate oxygen vacancies on-demand provides a tool for the exploration of mesoscale quantum phenomena and engineering multifunctional oxide devices.

Authors:
 [1];  [2];  [3]; ORCiD logo [1];  [1];  [4];  [1]; ORCiD logo [1]; ORCiD logo [5];  [2];  [1]
  1. Inst. for Basic Science (IBS), Seoul (Republic of Korea). Center for Correlated Electron Systems; Seoul National University (SNU), Seoul (Republic of Korea). Dept. of Physics and Astronomy
  2. Pennsylvania State Univ., University Park, PA (United States).Dept. of Materials Science and Engineering
  3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Science (CNMS); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Inst. for Functional Imaging of Materials
  4. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Science (CNMS); Sookmyung Women's Univ., Seoul (Republic of Korea). Dept. of Physics
  5. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Science (CNMS); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Inst. for Functional Imaging of Materials
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); Institute for Basic Science in Korea; National Science Foundation (NSF)
OSTI Identifier:
1407737
DOE Contract Number:
AC05-00OR22725; IBS-R009-D1; DMR-1410714; ERKCZ07
Resource Type:
Journal Article
Resource Relation:
Journal Name: Nature Communications; Journal Volume: 8; Journal Issue: 1
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; Surfaces, interfaces and thin films

Citation Formats

Das, Saikat, Wang, Bo, Cao, Ye, Rae Cho, Myung, Jae Shin, Yeong, Mo Yang, Sang, Wang, Lingfei, Kim, Minu, Kalinin, Sergei V., Chen, Long-Qing, and Noh, Tae Won. Controlled manipulation of oxygen vacancies using nanoscale flexoelectricity. United States: N. p., 2017. Web. doi:10.1038/s41467-017-00710-5.
Das, Saikat, Wang, Bo, Cao, Ye, Rae Cho, Myung, Jae Shin, Yeong, Mo Yang, Sang, Wang, Lingfei, Kim, Minu, Kalinin, Sergei V., Chen, Long-Qing, & Noh, Tae Won. Controlled manipulation of oxygen vacancies using nanoscale flexoelectricity. United States. doi:10.1038/s41467-017-00710-5.
Das, Saikat, Wang, Bo, Cao, Ye, Rae Cho, Myung, Jae Shin, Yeong, Mo Yang, Sang, Wang, Lingfei, Kim, Minu, Kalinin, Sergei V., Chen, Long-Qing, and Noh, Tae Won. Wed . "Controlled manipulation of oxygen vacancies using nanoscale flexoelectricity". United States. doi:10.1038/s41467-017-00710-5. https://www.osti.gov/servlets/purl/1407737.
@article{osti_1407737,
title = {Controlled manipulation of oxygen vacancies using nanoscale flexoelectricity},
author = {Das, Saikat and Wang, Bo and Cao, Ye and Rae Cho, Myung and Jae Shin, Yeong and Mo Yang, Sang and Wang, Lingfei and Kim, Minu and Kalinin, Sergei V. and Chen, Long-Qing and Noh, Tae Won},
abstractNote = {Oxygen vacancies, especially their distribution, are directly coupled to the electromagnetic properties of oxides and related emergent functionalities that have implications for device applications. Here using a homoepitaxial strontium titanate thin film, we demonstrate a controlled manipulation of the oxygen vacancy distribution using the mechanical force from a scanning probe microscope tip. By combining Kelvin probe force microscopy imaging and phase-field simulations, we show that oxygen vacancies can move under a stress-gradient-induced depolarisation field. When tailored, this nanoscale flexoelectric effect enables a controlled spatial modulation. In motion, the scanning probe tip thereby deterministically reconfigures the spatial distribution of vacancies. Finally, the ability to locally manipulate oxygen vacancies on-demand provides a tool for the exploration of mesoscale quantum phenomena and engineering multifunctional oxide devices.},
doi = {10.1038/s41467-017-00710-5},
journal = {Nature Communications},
number = 1,
volume = 8,
place = {United States},
year = {Wed Sep 20 00:00:00 EDT 2017},
month = {Wed Sep 20 00:00:00 EDT 2017}
}
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