Near-Room-Temperature Colossal Magnetodielectricity and Multiglass Properties in Partially Disordered La₂NiMnO₆, D. Choudhury, P. Mandal, R. Mathieu, A. Hazarika, S. Rajan, A. Sundaresan, U. V. Waghmare, R. Knut, O. Karis, P. Nordblad, and D. D. Sarma, Phys. Rev. Lett. 108, 127201 (2012).

We report magnetic, dielectric, and magnetodielectric responses of the pure monoclinic bulk phase of partially disordered La₂NiMnO₆, exhibiting a spectrum of unusual properties and establish that this compound is an intrinsically multiglass system with a large magnetodielectric coupling (8%–20%) over a wide range of temperatures (150–300 K). Specifically, our results establish a unique way to obtain colossal magnetodielectricity, independent of any striction effects, by engineering the asymmetric hopping contribution to the dielectric constant via the tuning of the relative-spin orientations between neighboring magnetic ions in a transition-metal oxide system. We discuss the role of antisite (Ni-Mn) disorder in emergence of these unusual properties.