Ferroelectric properties of hydrogen bonded order-disorder ferroelectric crystals

 

Aanchal Rawat and Trilok Chandra Upadhyay

 

Department of Physics, HNB Garhwal University (A Central University), Srinagar (Garhwal)

 

Uttarakhand-246174

 

E-mail: aanchalrawat324[at]gmail.com

 

In the present study we studied the ferroelectric properties of hydrogen bonded lead hydrogen phosphate type ferroelectric crystals. With the help of modified psedospin-lattice coupled mode model along with third and fourth order phonon interaction terms we obtained theoretical expressions for soft mode frequency, dielectric constant and loss tangent for these crystals. We fitted values of different parameters in the expressions to match the theoretical values of dielectric constant with experimental values of other researchers and theoretical values of loss tangent and soft mode frequency with experimentally correlated values. Thus we obtained values of different parameters appearing in the model Hamiltonian for the given ferroelectric crystals. The theoretical values values match well with the experimental values for these values of parameters.