On the role of intrinsic disorder in the structural phase transition of magnetoelectric EuTiO3

Details On the role of intrinsic disorder in the structural phase transition of magnetoelectric EuTiO3 On the role of intrinsic disorder in the structural phase transition of magnetoelectric EuTiO3

2011-11-02

arxiv.org/abs/1111.0541v2

Physics

Condensed Matter

Strongly Correlated Electrons

13 pages, 8 figures, 2 tables

Scientific paper

Up to now the crystallographic structure of the magnetoelectric perovskite EuTiO3 was considered to remain cubic down to low temperature. Here we present high resolution synchrotron X-ray powder diffraction data showing the existence of a structural phase transition, from cubic Pm-3m to tetragonal I4/mcm, involving TiO6 octahedra tilting, in analogy to the case of SrTiO3. The temperature evolution of the tilting angle indicates a second-order phase transition with an estimated Tc=235K. This critical temperature is well below the recent anomaly reported by specific heat measurement at TA\sim282K. By performing atomic pair distribution function analysis on diffraction data we provide evidence of a mismatch between the local (short-range) and the average crystallographic structures in this material. Below the estimated Tc, the average model symmetry is fully compatible with the local environment distortion but the former is characterized by a reduced value of the tilting angle compared to the latter. At T=240K data show the presence of local octahedra tilting identical to the low temperature one, while the average crystallographic structure remains cubic. On this basis, we propose intrinsic lattice disorder to be of fundamental importance in the understanding of EuTiO3 properties.

Affiliated with

Also associated with

No associations

Rating

On the role of intrinsic disorder in the structural phase transition of magnetoelectric EuTiO3 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with On the role of intrinsic disorder in the structural phase transition of magnetoelectric EuTiO3, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and On the role of intrinsic disorder in the structural phase transition of magnetoelectric EuTiO3 will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-329482