Ultrahigh-density ferroelectric data storage using scanning nonlinear dielectric microscopy

Ferroelectrics have generated considerable interest as promising storage media. In this paper, an investigation of ultrahigh-density ferroelectric data storage based on scanning nonlinear dielectric microscopy (SNDM) was carried out. For the purpose of obtaining fundamental knowledge of high-density ferroelectric data storage, several experiments on nanodomain formation in lithium tantalate (LiTaO₃) single crystal were conducted. As a result, a very small inverted domain with a radius of 6 nm was successfully formed in stoichiometric LiTaO₃ (SLT), and in addition, a domain dot array with an areal density of 1.5 Tbit/inch² was written on congruent LiTaO₃ (CLT). Additionally, the first prototype high-density ferroelectric data storage system was developed. Using this system, reading and writing data transfer rates were evaluated.