First-principles calculations of the epitaxial-strain phase diagram of perovskite SrCoO3 are presented. Through combination of the large spin-phonon coupling with polarization-strain coupling and coupling of the band gap to the polar distortion, both tensile and compressive epitaxial strain are seen to drive the bulk ferromagnetic-metallic (FM-M) phase to antiferromagnetic-insulating-ferroelectric (AFM-I-FE) phases, the latter having unusually low elastic energy. At these coupled magnetic-ferroelectric metal-insulator phase boundaries, cross responses to applied electric and magnetic fields and stresses are expected. In particular, a magnetic field or compressive uniaxial stress applied to the AFM phases could induce an insulator-metal transition, and an electric field applied to the FM-M phase could induce a metal-insulator transition.
@article{arxiv.1104.2856,
title = {Coupled magnetic-ferroelectric metal-insulator transitions in epitaxially-strained SrCoO$_{3}$ from first principles},
author = {Jun Hee Lee and Karin M. Rabe},
journal= {arXiv preprint arXiv:1104.2856},
year = {2012}
}