Magnetic and dielectric investigations of $\gamma$ - Fe${}_2$WO${}_6$

Abstract

The magnetic, thermodynamic and dielectric properties of the $\gamma$ - Fe${}_2$WO${}_6$ system is reported. Crystallizing in the centrosymmetric $Pbcn$ space group, this particular polymorph exhibits a number of different magnetic transitions, all of which are seen to exhibit a finite magneto-dielectric coupling. At the lowest measured temperatures, the magnetic ground state appears to be glass-like, as evidenced by the waiting time dependence of the magnetic relaxation. Also reflected in the frequency dependent dielectric measurements, these signatures possibly arise as a consequence of the oxygen non-stoichiometry, which promotes an inhomogeneous magnetic and electronic ground state.