Effects of Pressure and Electric Field on the Relaxational Dielectric Properties of K$_{0.97}$Li$_{0.03}$O$_{3}$ (KLT-3)*

The temperature dependence of the dielectric response of KLT-3 shows no evidence of a thermodynamic phase transition, but reveals two prominent relaxational features associated with the off-center Li$^{+}$ ion, one attributed to the hopping of the Li$^{+}$ dipole and the other with the reorientation of Li$^{+}$ - Li$^{+}$ ion pair. Both relaxations are Debye-like and follow Arrhenius kinetics, the energy barriers decreasing with pressure. While pressure favors the relaxational behavior, a biasing \textit{dc} electric field favors long-range order of the dipolar system. The interplay between pressure and field provides additional insight. Pressure suppresses the magnitude of the $\varepsilon \prime $(T) response over the whole temperature range The results allow evaluation of the contributions of the soft mode and of the Li$^{+}$ dipoles to the measured $\varepsilon \prime $(T) response.