Field dependent soft mode frequency in Ba_xSr_1-xTiO₃ferroelectric perovskites

300-305An expression has been obtained for the soft mode frequency in BaxSr1-xTiO3 ferroelectric perovskites in the presence of external electric field, by using double time temperature dependent Green’s function technique. The mass and force constant change due to impurity atoms which are taken into account in the presence of higher order anharmonic and electric moment terms in the Silverman Joseph Hamiltonian. The soft mode frequency is obtained in the presence of both the electric field and impurity of Ba in an anharmonic SrTiO3 ferroelectric perovskites. The soft mode frequency decreases with increase of impurity concentration of Ba in pure SrTiO3 . The soft mode frequency also increases with increase of external electric field in BaXSr1-XTiO3 ferroelectric perovskites.