Spontaneous electric polarization and Magneto-dielectric coupling in ceramic multiferroic Co3TeO6

TL;DR

This paper demonstrates the coexistence of spontaneous electric polarization and magneto-dielectric coupling in ceramic Co3TeO6, revealing complex interactions between magnetic and electric orders with potential multiferroic applications.

Contribution

It provides experimental evidence of magneto-electric and magneto-dielectric couplings in Co3TeO6, supporting recent theoretical predictions and highlighting spin-phonon coupling as a possible mechanism.

Findings

Dielectric constant anomaly at ~18K indicating spontaneous polarization

Weak ferromagnetic order observed at lower temperatures

Field and temperature dependence of ferroelectric transition

Abstract

We report observation of magneto-electric and magneto-dielectric couplings in ceramic Co3TeO6. Temperature dependent DC magnetization and dielectric constant measurements together indicate coupling between magnetic order and electronic polarization. Strong anomaly in dielectric constant at ~ 18K in zero magnetic field indicates presence of spontaneous polarization. Observations like weak ferromagnetic order at lower temperature, field and temperature dependences of the ferroelectric transition provide experimental verification of the recent theoretical proposal by P. Toledano et al., Phys. Rev. B 85, 214439 (2012). We provide direct evidence of spin-phonon coupling as possible origin of magnetic order.