Effects of strain on ferroelectric polarization and magnetism in orthorhombic HoMnO3

by Dr Diana Iusan (Uppsala University, Sweden)

Monday 20 May 2013, 16:00 → 18:00 Europe/Rome

Aula Conversi (Dipartimento di Fisica - Ed. G. Marconi)

We explore how the ferroelectric polarization of antiferromagnetic E type orthorhombic HoMnO3 can be increased, by investigating the effects of in-plane strain on both the magnetic properties and the ferroelectric polarization, using combined density functional theory calculations and a model Hamiltonian technique. Our results show that the net polarization is strongly enhanced under compressive strain, due to an increase of the electronic contribution to the polarization. In contrast, the ionic contribution is found to decrease. We identify the electron-lattice coupling, due to Jahn-Teller distortions, and its response to strain, to be responsible for the observed behavior.