Colossal Magnetocapacitance and Colossal Magnetoresistance inHgCr2S4

S. Weber, P. Lunkenheimer, R. Fichtl, J. Hemberger, V. Tsurkan, A. Loidl
2006 Physical Review Letters  
We present a detailed study of the dielectric and charge transport properties of the antiferromagnetic cubic spinel HgCr2S4. Similar to the findings in ferromagnetic CdCr2S4, the dielectric constant of HgCr2S4 becomes strongly enhanced in the region below 60 - 80 K, which can be ascribed to polar relaxational dynamics triggered by the onset of ferromagnetic correlations. In addition, the observation of polarization hysteresis curves indicates the development of ferroelectric order below about
more » ... K. Moreover, our investigations in external magnetic fields up to 5 T reveal the simultaneous occurrence of magnetocapacitance and magnetoresistance of truly colossal magnitudes in this material.
doi:10.1103/physrevlett.96.157202 pmid:16712192 fatcat:ywvtgwwrvffppglc7j3r5lmmry