Nanosized inverted domain dots in ferroelectric materials have potential applications in ultrahigh-density rewritable data storage systems. Here, a data storage system based on scanning nonlinear dielectric microscopy and thin films of ferroelectric single-crystal lithium tantalite is presented. Through domain engineering, nanosized inverted domain dots have been successfully formed at a data density of 1.50 Tbit/in.2.

Deposition of a hydrothermal method has a number of advantages; low deposition temperature, high-purity, deposition on a three-dimensional structure, and a large thickness. The present paper investigates the improvement of an epitaxial lead zirconate titanate (PZT) thin film deposited via hydrothermal synthesis. The critical parameter contributing to the film morphology was revealed to be the holding position of the reaction solution during deposition. In addition to this improvement, the SrRuO3 bottom electrode was confirmed to be able to withstand high alkali concentrations during the hydrothermal reaction. A hydrothermal synthesis time of 24 h yielded a PZT film with a thickness of 500 nm on SrRuO3/SrTiO3 (100) at 150 °C. The remanent polarization 2Pr and coercive electric field were 38.4 μC/cm2 and 21.8 kV/cm, respectively.

Deposition of thin films via hydrothermal method has various advantages: low deposition temperature, high purity, deposition on a three-dimensional structure, and a large thickness. Although an epitaxial lead zirconate titanate (PZT) thin-film deposition has been reported, the ferroelectric measurement has not been conducted due to the peel-off morphology of the film. The current paper investigates the improvement of an epitaxial PZT thin film deposited via a hydrothermal method. By adjusting the position at which the substrate was suspended in the solution, smooth morphology surface was successfully obtained. As a bottom electrode, a 200-nm SrRuO 3 thin film was deposited on SrTiO 3 single crystals, and the PZT thin film was deposited on SrRuO 3 . The remanent polarization 2Pr and coercive electric field for PZT on SrRuO 3 /SrTiO 3 (001) were 17.1 C/cm 2 and 36 kV/cm, respectively, and those of PZT on SrRuO 3 /SrTiO 3 (111) were 32.7 C/cm 2 and 59 kV/cm, respectively. The reason for large imprint electrical field, 91 kV/cm and 40 kV/cm for each film, was unclear at this stage, although it is associated with self-alignment poling direction. This self-alignment poling direction was confirmed via scanning nonlinear dielectric microscopy and is thought to have been related to the deposition mechanisms.

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A compact wideband millimeter wave detection element for the 35 GHz band has been developed mainly for passive imaging technologies. Using this element, fruit, timber, and foods in cardboard boxes have been observed nondestructively. The thermal radiation emitted from fruit changes as it is ripening, timber with knots and/or damages by white ants, and food temperature in cardboard box can be detected through incoherent passive imaging.Index Terms -Biomedical imaging, Imaging, Millimeter wave antenna arrays, Millimeter wave antennas, Millimeter wave imaging.