Annealing induced colossal magnetocapacitance and colossal magnetoresistance in In-doped CdCr2S4

TL;DR

This study demonstrates that annealing in cadmium vapor induces colossal magnetocapacitance and magnetoresistance in In-doped CdCr2S4, linked to an insulator-metal transition and Maxwell-Wagner effects near the Curie temperature.

Contribution

It reveals the correlation between CMC and CMR in In-doped CdCr2S4 and shows how annealing induces these effects through a combined mechanism.

Findings

Annealing induces CMC and CMR in In-doped CdCr2S4.

An insulator-metal transition occurs near the Curie temperature.

The effects are explained by CMR and Maxwell-Wagner effect.

Abstract

The correlation between colossal magnetocapacitance (CMC) and colossal magnetoresistance (CMR) in CdCr2S4 system has been revealed. The CMC is induced in polycrystalline Cd0.97In0.03Cr2S4 by annealing in cadmium vapor. At the same time, an insulator-metal transition and a concomitant CMR are observed near the Curie temperature. In contrast, after the same annealing treatment, CdCr2S4 displays a typical semiconductor behavior and does not show magnetic field dependent dielectric and electric transport properties. The simultaneous occurrence or absence of CMC and CMR effects implies that the CMC in the annealed Cd0.97In0.03Cr2S4 could be explained qualitatively by a combination of CMR and Maxwell-Wagner effect.