Embodiments relate to a piezoelectric ceramic and methods of making the same that is suitable for use as a high-power piezoelectric ceramic, and in particular a piezoelectric ceramic that exhibits both good hard properties and good soft properties. Embodiments involve generating the piezoelectric ceramic via the combination of chemical modification/doping and/or a texturing method so that the piezoelectric material exhibits a large figure of merit, as well as other hard and soft properties. The chemical modification involves Cu and Mn doping a piezoelectric material composition having a relaxor-lead titanate based ferroelectric structure. The texturing involves templated grain growth (TGG) texturing using a BaTiO.sub.3 (BT) template.

An apparatus includes a vibration member and a first cover disposed at a rear surface of the vibration member. The apparatus also includes a first vibration apparatus disposed at a rear surface of the first cover and configured to vibrate the vibration member. The apparatus includes a first enclosure member disposed at the rear surface of the first cover and at the rear surface of the vibration member. The apparatus also includes a first rear vibration member disposed at the first enclosure member.

Disclosed is a method of manufacturing an epitaxy oxide thin film of enhanced crystalline quality, and an epitaxy oxide thin film manufactured thereby according to the present invention. With respect to the manufacturing method of the epitaxy oxide thin film, which epitaxially grows an orientation film with an oxide capable of being oriented to (001), (110), and (111) on a single crystal Si substrate, because time required for raising a temperature of the orientation film up to an annealing temperature at room temperature is extremely minimized, thermal stress arising from the large difference in thermal expansion coefficients between the substrate and the orientation film is controlled, so crystalline quality of the epitaxy oxide thin film can be enhanced. Moreover, various epitaxial functional oxides are integrated into the thin film of enhanced crystalline quality so that a novel electronic device can be embodied.

A piezoelectric element includes, on a base, an underlying layer for controlling crystallinity of a piezoelectric layer, and the piezoelectric layer. The piezoelectric layer includes a crystal with an ABO.sub.3-type structure having at least Pb at A sites. In the underlying layer, an interface-with-the-base side is configured including at least Pb and another substance with a different composition rate from that of the piezoelectric layer at the A sites, and a substance with a different composition ratio from that of the piezoelectric layer at B sites. In a layer above the interface-with-the-base side in the underlying layer, the composition rate of the other substance included at the A sites of the underlying layer progressively changes and also the composition ratio of the substance included at the B sites progressively changes, from the interface-with-the-base side toward the interface-with-the-piezoelectric-layer side to approach the composition of the piezoelectric layer.

The ultrasound probe includes a piezoelectric element including a piezoelectric composition and an electrode that applies a voltage to the piezoelectric composition. The piezoelectric composition has piezoelectric characteristics expressed by any coordinates included in a region formed by a polyhedron having a plurality of predetermined points as vertexes in Cartesian coordinates (k.sub.eff, ε.sub.33.sup.S, E.sub.c) including variables k.sub.eff, ε.sub.33.sup.S and E.sub.c.

Disclosed is a piezoelectric element wherein a lower electrode made of Pt, a buffer layer made of PLT, and a piezoelectric thin film to be a perovskite ferroelectric thin film are formed in this order on a substrate. The average crystal grain size of Pt forming the lower electrode is not smaller than 50 nm and not larger than 150 nm.

A method for depolarization suppression of in rhombohedral relaxor-based ferroelectric single crystal. The purpose of the present invention is to address the problem that the rhombohedral relaxor-based ferroelectric single crystals would depolarize when driven to sufficiently electric field due to their low coercive field. In the present invention, the crystal cut, poling direction and compressive stress application direction of the crystal is selected based on the domain structure and anisotropic nature of the crystal such that the spontaneous direction(s) of the crystal would rotate towards the poling direction in response to the applied compressive stress. Through application of appropriate compressive stress, the magnitude of depolarization field of the rhombohedral relaxor-based ferroelectric single crystals can be effectively increased.

An optical transformer includes a plurality of light emitters, a plurality of photovoltaic cells positioned to receive light from at least a first subset of the plurality of light emitters, the plurality of photovoltaic cells including at least a first photovoltaic cell and a second photovoltaic cell, and one or more optically triggered switches positioned to receive light from at least a second subset of the plurality of light emitters, the one or more optically triggered switches including at least a first optically triggered switch electrically coupled to the first photovoltaic cell and the second photovoltaic cell. A method of operating the optical transformer is also described.

A transparent optical element may include a layer of an electroactive ceramic disposed between transparent electrodes, such that the electrodes are each oriented perpendicular to a non-polar direction of the ceramic layer. Optical properties of the optical element, including transmissivity, haze, and clarity may be improved by the application of a voltage to the electroactive ceramic, and an associated phase transformation.

An optical transformer includes a plurality of light emitters, a plurality of photovoltaic cells positioned to receive light from at least a first subset of the plurality of light emitters, the plurality of photovoltaic cells including at least a first photovoltaic cell and a second photovoltaic cell, and one or more optically triggered switches positioned to receive light from at least a second subset of the plurality of light emitters, the one or more optically triggered switches including at least a first optically triggered switch electrically coupled to the first photovoltaic cell and the second photovoltaic cell. A method of operating the optical transformer is also described.