Defect-Enhanced Polarization Switching in the Improper Ferroelectric LuFeO3

Petrucio Barrozo; Didrik René Småbråten; Yun-Long Tang; Bhagwati Prasad; Sahar Saremi; Rustem Ozgur; Vishal Thakare; Rachel A Steinhardt; Megan E Holtz; Vladimir Alexandru Stoica; Lane W Martin; Darrel G Schlom; Sverre Magnus Selbach; Ramamoorthy Ramesh

doi:10.1002/adma.202000508

Defect-Enhanced Polarization Switching in the Improper Ferroelectric LuFeO₃

Adv Mater. 2020 Jun;32(23):e2000508. doi: 10.1002/adma.202000508. Epub 2020 Apr 29.

Authors

Petrucio Barrozo^{1

2

3}, Didrik René Småbråten⁴, Yun-Long Tang^{2

3}, Bhagwati Prasad², Sahar Saremi², Rustem Ozgur², Vishal Thakare², Rachel A Steinhardt⁵, Megan E Holtz⁵, Vladimir Alexandru Stoica⁶, Lane W Martin^{2

3}, Darrel G Schlom⁵, Sverre Magnus Selbach⁴, Ramamoorthy Ramesh^{2

3}

Affiliations

¹ Physics Department, Federal University of Sergipe, São Cristóvão, Sergipe, 49100-000, Brazil.
² Department of Materials Science and Engineering and Department of Physics, University of California, Berkeley, CA, 94720, USA.
³ Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
⁴ Department of Materials Science and Engineering, NTNU Norwegian University of Science and Technology, Norway.
⁵ Department of Materials Science and Engineering, Cornell University, Ithaca, NY, 15805, USA.
⁶ Department of Materials Science and Engineering, Pennsylvania State University, University Park, PA, 16802, USA.

PMID: 32346899
DOI: 10.1002/adma.202000508

Abstract

Results of switching behavior of the improper ferroelectric LuFeO₃ are presented. Using a model set of films prepared under controlled chemical and growth-rate conditions, it is shown that defects can reduce the quasi-static switching voltage by up to 40% in qualitative agreement with first-principles calculations. Switching studies show that the coercive field has a stronger frequency dispersion for the improper ferroelectrics compared to a proper ferroelectric such as PbTiO₃ . It is concluded that the primary structural order parameter controls the switching dynamics of such improper ferroelectrics.

Keywords: LuFeO 3; ferroelectricity; h-LFO; multiferroics.

Abstract

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