DOPING OF PHOSPHORIC-ACID INTO FERROELECTRIC TRIGLYCINE SULFATE CRYSTAL

Single crystals of phosphoric-acid-doped triglycine sulfate (TGSP) wer e gown from solutions with various concentrations of H3PO4 The concent ration of dopant in the crystal and the P-E hystersis loop have been i nvestigated. The concentration in the crystal is much lower than that in solution. The incorporation of H3PO4 molecule is highly inhomogeneo us in the crystal and depends on the crystal growth sector. The doping generates no internal bias field and has no influence on the spontane ous polarization. Since the incorporated H3PO4 molecules act as obstac les to polarization switching, doping results in an the increase in co ercive field E(c). There is a distinct correlation between the intensi ty of E(c) and the concentration of H3PO4 in the crystal.