The hafnate perovskites PbHfO3(antiferroelectric) and SrHfO3(“potential” ferroelectric) are studied as epitaxial thin films on SrTiO3(001) substrates with the added opportunity of observing a morphotropic phase boundary (MPB) in the Pb1−
Searching for materials with room‐temperature electric‐field control of magnetism has interested researchers for many years with three‐dimensional perovskite BiFeO3‐based compounds as the main focus. Here we choose the layered hybrid improper ferroelectric Ruddlesden‐Popper oxides as a platform from which to realize electric field controllable magnetism, leveraging a recently identified strain tunable polar‐to‐nonpolar (P‐NP) transition. We first propose a design principle for selecting the required A and B cation chemistries that will ensure (001) A3B2O7films exhibit P‐NP transitions, which we substantiate with density functional calculations. By extending the guideline to B‐site ordered A3BB′O7oxides, we identify more compounds exhibiting P‐NP transitions marked by the disappearance of an in‐plane polarization that can be functionalized. We then demonstrate that weak ferromagnetism can be tuned by an electric field at the boundary of the P‐NP transition in B‐site ordered (001) A3BB′O7magnetic films, based on which we predict that cation ordered Ca3TcTiO7may be a viable candidate for room‐temperature electric‐field control of magnetism.
more » « less- NSF-PAR ID:
- 10037119
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 27
- Issue:
- 4
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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