Photo-induced phase transitions in ferroelectrics

Charles Paillard (1, 2) , Engin Torun (3) , Ludger Wirtz (3) , Laurent Bellaïche (4)

1 SPMS - Laboratoire Structures, Propriétés et Modélisation des solides
2 Department of Physics Department [Fayetteville]
3 Physics and Materials Science Research Unit
4 University of Arkansas [Fayetteville]

Ferroic materials naturally exhibit a rich number of functionalities, which often arise from thermally , chemically or mechanically induced symmetry breakings or phase transitions. Based on Density Functional Calculations, we demonstrate here that light can drive phase transitions as well in ferroelectric materials such as the perovskite oxides lead titanate and barium titanate. Phonon analysis and total energy calculations reveal that the polarization tends to vanish under illumination , to favor the emergence of non-polar phases, potentially antiferroelectric, and exhibiting a tilt of the oxygen octahedra. Strategies to tailor photo-induced phases based on phonon instabilities in the electronic ground state are also discussed.

Domaines: Science des matériaux [cond-mat.mtrl-sci]

Charles Paillard, Engin Torun, Ludger Wirtz, Laurent Bellaïche. Photo-induced phase transitions in ferroelectrics. Physical Review Letters, 2019, 123, pp.087601. ⟨10.1103/PhysRevLett.123.087601⟩. ⟨hal-02348316⟩