Spin correlated dielectric memory and rejuvenation in multiferroic CuCrS2

We report a rare consequence of memory effect in dielectric response (ϵ) and magnetic field induced rejuvenation in a relaxor-type multiferroic chalcogenide, CuCrS2. Despite reasonably high conductivity, we are able to detect significant spontaneous polarization using an improvised technique verifying ferroelectric (FE) order. Concomitant appearance of both FE and antiferromagnetic orders authenticates multiferroicity. A smeared out FE transition and strong frequency dependence of the broadened peak in ϵ obeying Dynamical scaling law signify relaxor properties. We discuss the role of geometrical frustration in the antiferromagnetically coupled layered triangular lattice and metal ligand hybridization for these unusual properties