Coupled Negative magnetocapacitance and magnetic susceptibility in a Kagome staircase-like compound Co3V2O8

TL;DR

This study investigates how magnetic fields influence the dielectric properties of Co3V2O8, revealing a negative magnetocapacitance linked to magnetic susceptibility, indicating a shared magnetostrictive mechanism.

Contribution

It reports the first observation of coupled negative magnetocapacitance and magnetic susceptibility in Co3V2O8, highlighting a different behavior from similar compounds.

Findings

Magnetic field suppresses dielectric anomaly above 6.1K.

Negative magnetocapacitance proportional to magnetic susceptibility.

Shared magnetostrictive origin for dielectric and magnetic responses.

Abstract

The dielectric constant of the Kagome staircase-like Co3V2O8 polycrystalline compound has been measured as function of temperature and magnetic field up to 14T. It is found that the application of an external magnetic field suppresses the anomaly for the dielectric constant beyond 6.1K. Furthermore, its magnetic field dependence reveals a negative magnetocapacitance which is proportional to the magnetic susceptibility, suggesting a common magnetostrictive origin for the magnetic field dependence of the two quantities. This result is very different from that obtained from the isostructural compound Ni3V2O8 that presents a peak in the dielectric constant at the incommensurate magnetic phase transition coupled to a sign change of the magnetocapacitance.