Electrical and optical measurements on nickel iodine boracite

Abstract

Abstract Measurements of resistivity, spontaneous polarization, pyroelectric coefficient, piezoelectricity, dielectric constant, spontaneous Faraday rotation, spontaneous birefringence and rotation of the optical indicatrix with temperature are reported. Between 4K and 61.5K a single ferroelectric/ferromagnetic/ferroelastic phase, consistent with Shubnikov point symmetry m′, exists.