Significance of isostructural distortion and strong magnetoelastic coupling in the weak ferromagnet YFe_0.9Cr_0.1O₃ Available to Purchase

We report the appearance of weak ferromagnetism above the long-range canted antiferromagnetic order T_N= 553 K at which the Fe-Cr interactions become dominant in YFe_0.9Cr_0.1O₃. The weak ferromagnetic order above T_N appears due to the increasing magnetic interactions in Fe-sublattices resulting in a canted antiferromagnetic transition at T_Fe-Fe = 620 K. Electrical hysteresis loop studies and Positive-Up Negative-Down protocol measurements reveal spontaneous but weak ferroelectricity in the system. Dielectric measurements as a function of temperature and frequency reveal a relaxorlike dielectric anomaly within a temperature interval of 400–500 K and anomalous signatures at and temperatures above T_N. Synchrotron x-ray diffraction studies over a broad temperature range, 298–873 K, illustrate a significant magnetoelastic coupling at T_N and around T_Fe-Fe. Isostructural distortions are further revealed over the temperature range of 400–500 K from the x-ray diffraction studies. Analyses of the diffraction patterns reveal the delicate interplay between the in-plane and out-of-plane exchange interactions over T_N and in isostructural distortion regions. We strongly argue that the ferroelectricity in YFe_0.9Cr_0.1O₃ results from the magnetostriction and Dzyaloshinskii-Moriya interaction manifested through a significant magnetoelastic coupling at T_N and T_Fe-Fe.