Interface enhancement of spin-polar phonon coupling in perovskite multiferroic superlattices
1 Key Laboratory of Quantum Information, University of Science and Technology of China Hefei, Anhui, 230026, PRC
2 Department of Physics and Institute for Computational Molecular Science, Temple University Philadelphia, PA 19122, USA
Received: 3 August 2012
Accepted: 7 September 2012
First-principles calculations are carried out for CaMnO3/BaTiO3 short-period superlattices with epitaxial strain corresponding to growth on a NdGaO3 substrate. The ferroelectricity and antiferrodistortion are analyzed under different magnetic orderings. It reveals that MnO6 octohedral rotation is greatly suppressed at the interfaces, which effectively increases the spin-polar phonon coupling in CaMnO3. Besides the conventional epitaxial-strain method, this mechanism provides an alternative way in engineering the spin-lattice coupling materials for an enhanced functionality.
PACS: 75.85.+t – Magnetoelectric effects, multiferroics / 77.80.bn – Strain and interface effects / 75.70.Cn – Magnetic properties of interfaces (multilayers, superlattices, heterostructures)
© EPLA, 2012