Charge-order-driven multiferroic properties of YCaMnO

Dielectric measurements on the charge-ordered insulators, Y 1−x Ca x MnO3 ( x = 0.4 , 0.45 and 0.5), show maxima in the dielectric constant around the charge ordering transition temperature while magnetic measurements show the presence of weak ferromagnetic interactions at low temperatures. Besides the magnetic field dependence of the dielectric constant, these manganites also exhibit second harmonic generation. Thus, the charge-ordered Y 1−x Ca x MnO3 compositions are multiferroic and magnetoelectric, in accordance with theoretical predictions. Magnetoelectric properties are retained in small particles of Y 0.5Ca0.5MnO3.