Dielectric Response in Ferroelectrics with Large Zero Point Energy at Low Temperature

An effective field approach has been used to study the influence of the zero-point energy on the of dielectric constant in ferroelectrics. The zero point energy was introduced to describe the effect of quantum fluctuation through the concept of quantum temperature scale. When the zero-point energy exists only at low temperature, and is large enough to depress the occurrence of ferroelectricity in the whole temperature range, the temperature dependence of the dielectric constant displays typical diffused phase transition characters. Furthermore, if the relaxation is of Debye-type, and the temperature dependence of the relaxation time has a similar form of the zero-point energy, main features of the frequency dispersion relation of the dielectric constant can be well reproduced for ferroelectric relaxors.

Keywords:

• Zero point energy
• dielectric constant
• ferroelectic relaxor

Acknowledgments

Paper originally presented at AMF-4, Bangalore, India, December 12-15, 2003;