Investigation of some temperature dependent ferroelectric properties of RDP crystal using double-time temperature dependent Green’s function technique and PLCM model

Abstract

Rubidium dihydrogen crystal’s (RDP, RbH2PO4) ferroelectric and dielectric properties have been analyzed in the present paper. This crystal belongs to the family of KDP-type ferroelectric and has been extensively studied because of peculiar properties in the area of ferroelectrics. In the present study, we have added some higher-order anharmonic terms in the pseudospin lattice coupled mode model (PLCM) for RDP crystal and have used Green’s function technique to solve our different expressions here discussed. We have computed expressions for soft mode frequency, dielectric constant, and loss tangent. We have shown variation of these three properties with temperature and discussed their crystal structure before and after their ferroelectric transition point. We have used model constants from Ganguli. For a suitable temperature range variation of temperature and dielectric constant according to Curie-Weiss behavior can be seen in our result. We have also verified our obtained results to the experimental analysis.