Abstract

Ultrasonic velocity measurements are used to examine the elastic properties of the magnetoelectric compound $\mathrm{Cu}\mathrm{Fe}{\mathrm{O}}_{2}$ in the vicinity of the magnetic and structural phase transitions near $14\phantom{\rule{0.3em}{0ex}}\mathrm{K}$. Strong softening of modes related to ${C}_{66}$ occurs at the transition from the high-temperature rhombohedral $R\overline{3}m$ to lower-temperature monoclinic $C2∕m$ symmetry. A Landau free energy is proposed and analyzed in order to understand the elastic properties of $\mathrm{Cu}\mathrm{Fe}{\mathrm{O}}_{2}$. The principal features of sound velocity modes vs temperature are reproduced by the model. Our analysis suggests that the transition at $14\phantom{\rule{0.3em}{0ex}}\mathrm{K}$ is primary pseudoproper ferroelastic, with the spin acting as a secondary order parameter.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.