Electrostatic memory in KTaO3

Perovskite oxide materials with strong spin–orbit coupling (SOC) have tremendous potential for next generation spin-electronic devices. In this work, we present the creation of artificial electrical domains on the conducting surface of KTaO3 (KTO) having strong SOC. A conductive atomic force microscopy tip has been used to induce extremely small electrically active charge domains on the surface of KTO. The versatility of creating such nanodomains is that the features can be written and erased with nanometer scale precision. The written signal (phase difference between the written and unwritten regions) on KTO has turned out to be much higher than that on other reported perovskite oxides. Kelvin probe force microscopy measurements are performed to probe the surface potential and work function changes in the regions of nano-electrical domains. Magnetic force microscopy measurements suggest generation of a magnetic field when electrostatic charge is written in a dipolar configuration which can be utilized in future nano-electric devices.