Ferroelectric field control of charge density in oxide films with polarization reversal by electric double layer

摘要

We demonstrate the ferroelectric field control of transport properties in SrRuO3 and Nb-doped SrTiO3.We utilize ionic liquid for the polarization reversal of PbZr0.2Ti0.8O3. The modulation of the sheet resistance in SrRuO3 is close to the value expected from the polarization-voltage measurement for PbZr0.2Ti0.8O3. In the case of Nb-doped SrTiO3, carrier density for the two polarization states is obtained by the Hall measurement, elucidating modulation of carrier density by 8.0 x 10(13 )cm(-2) at 150K. These results indicate that polarization reversal via the electric double layer can control the carrier density of materials beneath the ferroelectric layer similarly to conventional switching techniques utilizing a metal top electrode or a metallic tip of a piezoresponse force microscopy. Published by AIP Publishing.