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Title: Enhanced spontaneous polarization in double perovskite Bi 2 FeCrO 6 films
Abstract

We report the pulsed‐laser deposition of epitaxial double‐perovskite Bi2FeCrO6(BFCO) films on the (001)‐, (110), and (111)‐oriented single‐crystal SrTiO3substrates. All of the BFCO films with various orientations show theandsuperlattice‐diffraction peaks. The intensity ratios between the‐superlattice and the main 111‐diffraction peak can be tailored by simply adjusting the laser repetition rate and substrate temperature, reaching up to 4.4%. However, both optical absorption spectra and magnetic measurements evidence that the strong superlattice peaks are not correlated with theB‐site Fe3+/Cr3+cation ordering. Instead, the epitaxial (111)‐oriented Bi2FeCrO6films show an enhanced remanent polarization of 92 μC/cm2at 10 K, much larger than the predicted values by density‐functional theory calculations. Positive‐up‐negative‐down (PUND) measurements with a time interval of 10 μs further support these observations. Therefore, our experimental results reveal that the strong superlattice peaks may come fromA‐ orB‐site cation shifts along the pseudo‐cubic [111] direction, which further enhance the ferroelectric polarization of the BFCO thin films.

 
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Award ID(s):
1708615
PAR ID:
10371474
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
Journal of the American Ceramic Society
Volume:
102
Issue:
9
ISSN:
0002-7820
Page Range / eLocation ID:
p. 5234-5242
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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