Origin of natural and magnetic field induced polar order in orthorhombic <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>Pr</mml:mi><mml:msub><mml:mi>Fe</mml:mi><mml:mrow><mml:mn>1</mml:mn><mml:mo>/</mml:mo><mml:mn>2</mml:mn></mml:mrow></mml:msub><mml:msub><mml:mi>Cr</mml:mi><mml:mrow><mml:mn>1</mml:mn><mml:mo>/</mml:mo><mml:mn>2</mml:mn></mml:mrow></mml:msub><mml:msub><mml:mi mathvariant="normal">O</mml:mi><mml:mn>3</mml:mn></mml:msub></mml:mrow></mml:math>
Anil Kumar, M. Kamal Warshi, Archna Sagdeo, M. Krzystyniak, Svemir Rudić, D. T. Adroja, Iván da Silva, Pankaj R. Sagdeo
Abstract
Here, we report the possible origin of natural and magnetic field induced polar order near room temperature (RT) in $\mathrm{Pr}{\mathrm{Fe}}_{1/2}{\mathrm{Cr}}_{1/2}{\mathrm{O}}_{3}$. The temperature-dependent Raman spectroscopy (RS) and synchrotron x-ray diffraction experiments disregard any change in the structure at low temperatures, which is not compatible with the emergence of natural ferroelectricity in this sample. Further, inelastic neutron scattering, neutron Compton scattering, neutron resonance transmission analysis and magnetic field-dependent RS experiments, suggest an increase in the delocalization of ${\mathrm{Pr}}^{3+}$ ions in $\mathrm{Pr}{\mathrm{Fe}}_{1/2}{\mathrm{Cr}}_{1/2}{\mathrm{O}}_{3}$ with respect to the parent compound $\mathrm{PrFe}{\mathrm{O}}_{3}$. The evaluation of the present results reveals that more delocalized ${\mathrm{Pr}}^{3+}$ ions and strong spin-phonon coupling in $\mathrm{Pr}{\mathrm{Fe}}_{1/2}{\mathrm{Cr}}_{1/2}{\mathrm{O}}_{3}$ seem to be a driving force for the observed natural and magnetic field induced switchable polar order in $\mathrm{Pr}{\mathrm{Fe}}_{1/2}{\mathrm{Cr}}_{1/2}{\mathrm{O}}_{3}$. The present results provide a significant contribution in understanding the ferroelectric polarization and progress in the search for RT magnetodielectric materials.