Multiferroicity in half-Cr-doped YMnO3 epitaxial films with compressive strain

Abstract

We report on the growth and characterization of epitaxial (010)- and (100)-YMn0.5Cr0.5O3 films on the corresponding YAlO3 substrates. It is found that the magnetic transition temperature increases from 75 K for the bulk sample to 120 K for the compressive-strained films. Along the c- and a-axes, ferroelectric polarization develops below 120 K with the saturation values of 0.17 and 0.05 μC/cm2, respectively, while it remains zero along the b-axis. Furthermore, it is demonstrated that the ferroelectric polarization can be modulated by magnetic field. The displayed ferroelectricity is explainable by considering coexistence of the predominant bc-cycloidal and minor E-type antiferromagnetic orders.

The magnetic transition temperature tuned by strain in YMn0.9Ru0.1O3 thin films

“…31 In addition, M-T curves display that there are two kinks at T N1 = 49 K and T N2 = 117 K, respectively, which is similar to the previous reported YMCO films. 32 The two magnetic transitions may correspond to different kinds of stain states. The marked antiferromagnetic transition T N1 is close to that of orthorhombic YMnO 3 bulk.…”

“…Comparatively, for the higher T N2 , there is a conspicuous increase from 117 K to 131 K with decreasing the thickness, which could be attributed to the in-plane strain of the film. 32 The expansion of in-plane Mn-O bonds could disturb the E-type antiferromagnetic ordering along [010] axis. According to the above results of Raman scattering, the stretching of in-plane oxygen atoms around Mn atom is enhanced with decreasing the thickness of the film.…”