Evidence for a strong spin-lattice coupling in multiferroic HoMnO 3 is derived from thermal expansion measurements along the a and c axes. The magnetoelastic effect results in sizable anomalies of the thermal expansivities at the antiferromagnetic (T N) and the spin rotation (T SR) transition temperatures as well as in a negative c-axis expansivity below room temperature. The coupling between magnetic orders and dielectric properties below T N is explained by the lattice strain induced by the magnetoelastic effect. At T SR various physical quantities show discontinuities that are thermodynamically consistent with a first-order phase transition.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - 2005 Feb|
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics