Dielectric properties of V2O3 and (V0.989Cr0.011)2O3 from temperature-dependent ac impedance measurements

The dielectric properties of the various insulating phases in pure V2O3 and (V0.989Cr0.011)2O3 crystals have been investigated. Large dielectric constants on the scale of 103 were obtained, which were attributed to the backflow effect of normal carriers and also the periodic charge configuration relevant to V-V dimers in an antiferromagnetic insulating state or the bond contraction of V-Cr-V in a paramagnetic insulating phase. We propose that if Cr dopants are arranged nearly uniformly, the charge density of (V0.989Cr0.011)2O3 in the paramagnetic insulating phase will exhibit a doping-induced wavelike distribution in real space, and thus the polarization of the system will be enhanced.

Automated summary

The dielectric properties of the various insulating phases in pure V2O3 and (V0.989Cr0.011)2O3 crystals were investigated. Large dielectric constants on the scale of 10^3 were obtained, attributed to the backflow effect of normal carriers and the periodic charge configuration relevant to V-V dimers in an antiferromagnetic insulating state or the bond contraction of V-Cr-V in a paramagnetic insulating phase. It is proposed that if Cr dopants are arranged nearly uniformly, the charge density of (V0.989Cr0.011)2O3 in the paramagnetic insulating phase will exhibit a doping-induced wavelike distribution in real space, enhancing the system's polarization.