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Title: Artificial two-dimensional polar metal at room temperature

Abstract

© 2018 The Author(s). Polar metals, commonly defined by the coexistence of polar crystal structure and metallicity, are thought to be scarce because the long-range electrostatic fields favoring the polar structure are expected to be fully screened by the conduction electrons of a metal. Moreover, reducing from three to two dimensions, it remains an open question whether a polar metal can exist. Here we report on the realization of a room temperature two-dimensional polar metal of the B-site type in tri-color (tri-layer) superlattices BaTiO3/SrTiO3/LaTiO3. A combination of atomic resolution scanning transmission electron microscopy with electron energy-loss spectroscopy, optical second harmonic generation, electrical transport, and first-principles calculations have revealed the microscopic mechanisms of periodic electric polarization, charge distribution, and orbital symmetry. Our results provide a route to creating all-oxide artificial non-centrosymmetric quasi-Two-dimensional metals with exotic quantum states including coexisting ferroelectric, ferromagnetic, and superconducting phases.

Authors:
; ; ; ; ; ; ; ; ; ; ; ; ; ORCiD logo; ; ; ; ;
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1460354
DOE Contract Number:  
AC02-05CH11231
Resource Type:
Journal Article
Journal Name:
Nature Communications
Additional Journal Information:
Journal Volume: 9; Journal Issue: 1; Journal ID: ISSN 2041-1723
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English

Citation Formats

Cao, Yanwei, Wang, Zhen, Park, Se Young, Yuan, Yakun, Liu, Xiaoran, Nikitin, Sergey M., Akamatsu, Hirofumi, Kareev, M., Middey, S., Meyers, D., Thompson, P., Ryan, P. J., Shafer, Padraic, N’Diaye, A., Arenholz, E., Gopalan, Venkatraman, Zhu, Yimei, Rabe, Karin M., and Chakhalian, J. Artificial two-dimensional polar metal at room temperature. United States: N. p., 2018. Web. doi:10.1038/s41467-018-03964-9.
Cao, Yanwei, Wang, Zhen, Park, Se Young, Yuan, Yakun, Liu, Xiaoran, Nikitin, Sergey M., Akamatsu, Hirofumi, Kareev, M., Middey, S., Meyers, D., Thompson, P., Ryan, P. J., Shafer, Padraic, N’Diaye, A., Arenholz, E., Gopalan, Venkatraman, Zhu, Yimei, Rabe, Karin M., & Chakhalian, J. Artificial two-dimensional polar metal at room temperature. United States. doi:10.1038/s41467-018-03964-9.
Cao, Yanwei, Wang, Zhen, Park, Se Young, Yuan, Yakun, Liu, Xiaoran, Nikitin, Sergey M., Akamatsu, Hirofumi, Kareev, M., Middey, S., Meyers, D., Thompson, P., Ryan, P. J., Shafer, Padraic, N’Diaye, A., Arenholz, E., Gopalan, Venkatraman, Zhu, Yimei, Rabe, Karin M., and Chakhalian, J. Wed . "Artificial two-dimensional polar metal at room temperature". United States. doi:10.1038/s41467-018-03964-9. https://www.osti.gov/servlets/purl/1460354.
@article{osti_1460354,
title = {Artificial two-dimensional polar metal at room temperature},
author = {Cao, Yanwei and Wang, Zhen and Park, Se Young and Yuan, Yakun and Liu, Xiaoran and Nikitin, Sergey M. and Akamatsu, Hirofumi and Kareev, M. and Middey, S. and Meyers, D. and Thompson, P. and Ryan, P. J. and Shafer, Padraic and N’Diaye, A. and Arenholz, E. and Gopalan, Venkatraman and Zhu, Yimei and Rabe, Karin M. and Chakhalian, J.},
abstractNote = {© 2018 The Author(s). Polar metals, commonly defined by the coexistence of polar crystal structure and metallicity, are thought to be scarce because the long-range electrostatic fields favoring the polar structure are expected to be fully screened by the conduction electrons of a metal. Moreover, reducing from three to two dimensions, it remains an open question whether a polar metal can exist. Here we report on the realization of a room temperature two-dimensional polar metal of the B-site type in tri-color (tri-layer) superlattices BaTiO3/SrTiO3/LaTiO3. A combination of atomic resolution scanning transmission electron microscopy with electron energy-loss spectroscopy, optical second harmonic generation, electrical transport, and first-principles calculations have revealed the microscopic mechanisms of periodic electric polarization, charge distribution, and orbital symmetry. Our results provide a route to creating all-oxide artificial non-centrosymmetric quasi-Two-dimensional metals with exotic quantum states including coexisting ferroelectric, ferromagnetic, and superconducting phases.},
doi = {10.1038/s41467-018-03964-9},
journal = {Nature Communications},
issn = {2041-1723},
number = 1,
volume = 9,
place = {United States},
year = {2018},
month = {4}
}

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