Evidence of Magneto-Dielectric Coupling at Room Temperature in Polycrystalline KBiFe2O5

Abstract

The phase pure polycrystalline KBiFe2O5 with space group P2/c is synthesized following solid state reaction route. The temperature dependent real and imaginary part of dielectric constant is studied over wide temperature (26˚C to 580˚C) and frequency range (100 Hz ≤ f ≤1 MHz). Two distinct anomalies at around 110˚C and 510˚C is observed in both real (ε) an imaginary (tanδ) part of dielectric constant which can be attributed to Maxwell-Wagner effect. Our DC susceptibility measurement up to room temperature does not show any transition even up to room temperature, giving an indication that its transition temperature is above room temperature. This aspect is further confirmed from M-H hysteresis loop which shows a weak ferromagnetic hysteresis loop at room temperature. The evidence of magnetodielectric (MD) coupling at room temperature is confirmed from magnetic field dependent dielectric measurement in the form of inverted butterfly shaped ε-H loop.