Stress-Induced Quantum Ferroelectricity in SrTiO₃

Abstract

Through observation of the optical second harmonic generation, the stress-induced ferroelectric transition temperature of SrTiO₃ was determined as a function of the applied uniaxial stress along the [100] direction. The characteristics of the temperature-stress phase diagram are in agreement with the theoretical prediction of the critical behavior of the quantum ferroelectricity.