Phase transition in potassium dihydrogen phosphate induced by an applied static electric field.

Abstract

Raman scattering experiments show that the potassium dihydrogen phosphate (KDP) crystal undergoes a phase transition at 20 K induced by a static electric field applied along the [001] direction relative to the orthorhombic structure. Qualitative changes occur in the Raman spectra of $X(\mathrm{ZX})Y$ and $X(\mathrm{YZ})Y$ scattering geometries for applied dc electric field intensities of the order of 4.7 kV/cm or higher. The phase transition exhibits an irreversible character similar to that presented by KDP under uniaxial pressure at 110 K.