Anomalous dielectric behavior in nanoparticle Eu2O3:SiO2 glass composite system
Department of Physics and Center for Nanoscience and Nanotechnology, National Sun Yat-Sen University Kaohsiung, 804 Taiwan
Accepted: 17 November 2010
Eu2O3 (0.5 mol%) nanoparticles have been synthesized in a silica glass matrix by the sol-gel method at calcination temperatures of 700 °C and above. Compared with the parent material SiO2, this nano-glass composite system shows enhancement of dielectric constant and diffuse phase transition along with magnetodielectric effect around room temperature (∼270 K). The observed conduction mechanism is found to be closely related to the thermally activated oxygen vacancies. Magnetodielectric behavior is strongly associated with magnetoresistance changes, depending on the nanoparticle size and separation. Such a material might be treated as a potential candidate for device miniaturization.
PACS: 75.50.Tt – Fine-particle systems; nanocrystalline materials / 77.55.D- – High-permittivity gate dielectric films / 75.85.+t – Magnetoelectric effects, multiferroics
© EPLA, 2010