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Title: Designing iridate-based superlattice with large magnetoelectric coupling
The coupling between ferroelectric and magnetic order provides a powerful means to control magnetic properties with electric fields. In this study, we have investigated the magnetoelectric (ME) coupling in iridate-oxide based superlattices employing first-principles density functional theory (DFT) calculations. In particular, we have investigated several oxide superlattices, including (SrIrO 3 ) 1 –(CaTiO 3 ) 1 (SIO–CTO) and (SrIrO 3 ) 1 –(BaTiO 3 ) 1 (SIO–BTO), with an alternating single layer of SIO and CTO/BTO. We identify a very large ME coupling in SIO–BTO mediated by both lattice and electronic contributions. In comparison, moderate ME coupling constants are found in SIO–CTO. Further electronic and structural analyses reveal that the large ME coupling of SIO–BTO is caused by the large spin–orbit coupling of 5d iridium as well as the significant polarization induced in the SIO–BTO. Interestingly, we find that the ME coupling in SIO–BTO can further be enhanced by modulating epitaxial strain. These results suggest a route to significantly enhance the ME coupling effects, which might be applicable for other materials and practical applications.  more » « less
Award ID(s):
1848269
PAR ID:
10142860
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Journal of Materials Chemistry C
Volume:
7
Issue:
42
ISSN:
2050-7526
Page Range / eLocation ID:
13294 to 13300
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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