Study of the proton-beam irradiation effects on TlH2PO4

The H+-ion treatment effect on TlH2PO4, a KH2PO4 (KDP)-type ferroelectrics, was studied by nuclear magnetic resonance (NMR) and AC dielectric constant measurements. A sample of TlH2PO4 was irradiated by 1-MeV H+ ion beams to a dose of 1015 ions/cm2. The change in the NMR relaxation behaviors after the irradiation was attributed that in the hydrogen-bond geometry, presumably affecting the order–disorder proton dynamics. A prominent decrease in the dielectric constant was also observed after the irradiation. The macroscopic and microscopic changes due to the irradiation are discussed in the light of the proton dynamics.