Title :
Relaxor ferroelectric like high dielectric constant in SmCrO3 semiconductor ceramics
Author :
Prasad, Bandi Vitta ; Rao, B. Venugopa ; Babu, D. Suresh ; Rao, G. Narsinga ; Chen, J.W.
Author_Institution :
Dept. of Phys., Mahatma Gandhi Inst. of Technol., Hyderabad, India
Abstract :
The dielectric properties and impedance spectroscopy (IS) of perovskite SmCrO3 ceramics were studied in the frequency range of 100Hz 1MHz in the temperature range from 80 K to 300 K. These materials exhibited colossal dielectric constant value of ~ 104 at room temperature. The response is similar to that observed for relaxor-ferroelectrics. IS data analysis indicates the ceramics to be electrically heterogeneous semiconductors consisting of semiconducting grains with dielectric constant 10 and more resistive grain boundaries. We conclude, therefore that grain boundary effect is the primary source for the high effective dielectric constant in SmCrO3 ceramics.
Keywords :
dielectric losses; dielectric polarisation; dielectric relaxation; electrical resistivity; ferroelectric ceramics; ferroelectric semiconductors; grain boundaries; permittivity; relaxor ferroelectrics; samarium compounds; space charge; SmCrO3; dielectric loss tangent; dielectric polarization; dielectric properties; electrical resistivity; electrically heterogeneous semiconductors; frequency 100 Hz to 1 MHz; grain boundaries; high colossal dielectric constant; impedance spectroscopy; perovskite semiconductor ceramics; relaxor ferroelectrics; semiconducting grains; space charge; temperature 80 K to 300 K; Ceramics; Fitting; Welding; Ceramics; Dielectric Properties; Impedance spectroscopy; Sol-gel chemistry;
Conference_Titel :
Nanoscience, Engineering and Technology (ICONSET), 2011 International Conference on
Conference_Location :
Chennai
Print_ISBN :
978-1-4673-0071-1
DOI :
10.1109/ICONSET.2011.6167969
