Atomic scale crystal field mapping of polar vortices in oxide superlattices

Susarla, Sandhya; García-Fernández, Pablo; Ophus, Colin; Das, Sujit; Aguado-Puente, Pablo; McCarter, Margaret; Ercius, Peter; Martin, Lane W.; Ramesh, Ramamoorthy; Junquera, Javier

doi:10.1038/s41467-021-26476-5

Title: Atomic scale crystal field mapping of polar vortices in oxide superlattices

Abstract

Polar vortices in oxide superlattices exhibit complex polarization topologies. Using a combination of electron energy loss near-edge structure analysis, crystal field multiplet theory, and first-principles calculations, we probe the electronic structure within such polar vortices in [(PbTiO₃)₁₆/(SrTiO₃)₁₆] superlattices at the atomic scale. The peaks in Ti L-edge spectra shift systematically depending on the position of the Ti⁴⁺ cations within the vortices i.e., the direction and magnitude of the local dipole. First-principles computation of the local projected density of states on the Ti 3d orbitals, together with the simulated crystal field multiplet spectra derived from first principles are in good agreement with the experiments.

Authors:

^[1];

^[2];

^[3]; Das, Sujit ^[4];

^[5]; McCarter, Margaret ^[1];

^[3];

^[6];

^[2]

Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States)
Univ. of Cantabria, Santander, Cantabria (Spain)
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Univ. of California, Berkeley, CA (United States)
CIC nanoGUNE BRTA (Spain)
Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

Publication Date:: 2021-11-01

Research Org.:: Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

Sponsoring Org.:: USDOE Office of Science (SC), Basic Energy Sciences (BES), Scientific User Facilities Division

OSTI Identifier:: 1829704

Grant/Contract Number:: AC02-05CH11231

Resource Type:: Accepted Manuscript

Journal Name:: Nature Communications

Additional Journal Information:: Journal Volume: 12; Journal Issue: 1; Journal ID: ISSN 2041-1723

Publisher:: Nature Publishing Group

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE

Citation Formats


                    Susarla, Sandhya, García-Fernández, Pablo, Ophus, Colin, Das, Sujit, Aguado-Puente, Pablo, McCarter, Margaret, Ercius, Peter, Martin, Lane W., Ramesh, Ramamoorthy, and Junquera, Javier. Atomic scale crystal field mapping of polar vortices in oxide superlattices.  United States: N. p., 2021. 
Web.  doi:10.1038/s41467-021-26476-5.

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                    Susarla, Sandhya, García-Fernández, Pablo, Ophus, Colin, Das, Sujit, Aguado-Puente, Pablo, McCarter, Margaret, Ercius, Peter, Martin, Lane W., Ramesh, Ramamoorthy, & Junquera, Javier. Atomic scale crystal field mapping of polar vortices in oxide superlattices.  United States.  https://doi.org/10.1038/s41467-021-26476-5

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                    Susarla, Sandhya, García-Fernández, Pablo, Ophus, Colin, Das, Sujit, Aguado-Puente, Pablo, McCarter, Margaret, Ercius, Peter, Martin, Lane W., Ramesh, Ramamoorthy, and Junquera, Javier. Mon .  
"Atomic scale crystal field mapping of polar vortices in oxide superlattices".  United States.  https://doi.org/10.1038/s41467-021-26476-5.  https://www.osti.gov/servlets/purl/1829704.

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@article{osti_1829704,

  title        = {Atomic scale crystal field mapping of polar vortices in oxide superlattices},

  author       = {Susarla, Sandhya and García-Fernández, Pablo and Ophus, Colin and Das, Sujit and Aguado-Puente, Pablo and McCarter, Margaret and Ercius, Peter and Martin, Lane W. and Ramesh, Ramamoorthy and Junquera, Javier},

  abstractNote = {Polar vortices in oxide superlattices exhibit complex polarization topologies. Using a combination of electron energy loss near-edge structure analysis, crystal field multiplet theory, and first-principles calculations, we probe the electronic structure within such polar vortices in [(PbTiO3)16/(SrTiO3)16] superlattices at the atomic scale. The peaks in Ti L-edge spectra shift systematically depending on the position of the Ti4+ cations within the vortices i.e., the direction and magnitude of the local dipole. First-principles computation of the local projected density of states on the Ti 3d orbitals, together with the simulated crystal field multiplet spectra derived from first principles are in good agreement with the experiments.},

  doi          = {10.1038/s41467-021-26476-5},

  journal      = {Nature Communications},

  number       = 1,

  volume       = 12,

  place        = {United States},

  year         = {2021},

  month        = {11}

}

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Title: Atomic scale crystal field mapping of polar vortices in oxide superlattices

Abstract

Citation Formats

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