A magnetoelectric energy harvester having excellent power generation performance and a manufacturing method thereof are provided. The magnetoelectric energy harvester includes a magnetostrictive material portion including a magnetostrictive material which generates a mechanical deformation when being magnetized. The magnetoelectric energy harvester also includes a piezoelectric material portion which has a bending vibration mode and includes a piezoelectric material which produces power by receiving a mechanical deformation force from the magnetostrictive material portion.

A piezoelectric material that has good insulating properties and piezoelectricity and is free of lead and potassium and a piezoelectric element that uses the piezoelectric material are provided. The piezoelectric material contains copper and a perovskite-type metal oxide represented by general formula (1): (1?x){(Na.sub.yBa.sub.1?z)(Nb.sub.zTi.sub.1?z) O.sub.3}-xBiFeO.sub.3 (where 0<x?0.015, 0.80?y?0.95, and 0.85 ?z?0.95). In the piezoelectric material, 0.04 mol % or more and 2.00 mol % or less of Cu is contained relative to 1 mol of the perovskite-type metal oxide. Also provided is a piezoelectric element that includes a first electrode, a piezoelectric material, and a second electrode, in which the piezoelectric material described above is used as the piezoelectric material.

A method for driving a piezoelectric element including a first electrode, a piezoelectric layer formed on the first electrode and containing a composite oxide of an ABO.sub.3 type perovskite structure, and a second electrode formed on the piezoelectric layer, and the method includes driving the piezoelectric element by applying a signal having a predetermined driving waveform by a predetermined number of times, and driving the piezoelectric element by applying a signal having the predetermined driving waveform in reverse polarity.

An article comprising a ferroelectric material in its ferroelectric phase, wherein the article is configured to enable low-loss propagation of signals with ultra-low dielectric loss at one or more select frequencies.

An electronic device may include a first electrode, a first magnetostrictive layer coupled to the first electrode, a plurality of alternating ferromagnetic and insulating layers stacked above the first magnetostrictive layer, a second electrode electrically coupled to an intermediate ferromagnetic layer in the stack of ferromagnetic and insulating layers, a second magnetostrictive layer above the stack of ferromagnetic and insulating layers, and a third electrode electrically coupled to the second magnetostrictive layer. At least one ferromagnetic layer below the intermediate ferromagnetic layer may be switchable between different polarization states responsive to a first voltage applied across the first and second electrodes, and at least one ferromagnetic layer above the intermediate ferromagnetic layer may be switchable between different polarization states responsive to a second voltage applied across the second and third electrodes.

To produce a ferroelectric film formed of a lead-free material. The ferroelectric film according to an aspect of the present invention includes a (K.sub.1-XNa.sub.X)NbO.sub.3 film or a BiFeO.sub.3 film having a perovskite structure and a crystalline oxide preferentially oriented to (001) formed on at least one of the upper side and lower side of the (K.sub.1-XNa.sub.X)NbO.sub.3 film or BiFeO.sub.3 film, and X satisfies the formula below
0.3X0.7.

A piezoelectric thin film contains a metal oxide having a perovskite structure. The metal oxide contains bismuth, potassium, titanium, magnesium, iron, and an element M. The element M is at least one element selected from the group consisting of gallium and cobalt. At least a part of the metal oxide is at least one crystal selected from the group consisting of a tetragonal crystal and an orthorhombic crystal. A (001) plane of the crystal is oriented in a normal direction of a surface of the piezoelectric thin film.

A liquid-ejecting head includes a pressure-generating chamber communicating with a nozzle opening, and a piezoelectric element. The piezoelectric element has piezoelectric layer contains a perovskite complex oxide containing Bi, La, Fe, and Mn and can undergo electric-field-induced phase transition.

Provided is an ultrasonic motor including an annular vibrator and an annular moving member that is brought into pressure-contact with the vibrator. The vibrator includes an annular vibrating plate and an annular piezoelectric element. The piezoelectric element includes an annular lead-free piezoelectric ceramic piece, a common electrode arranged on one surface of the piezoelectric ceramic piece, and a plurality of electrodes arranged on the other surface of the piezoelectric ceramic piece. The plurality of electrodes include two drive phase electrodes, one or more non-drive phase electrodes, and one or more detection phase electrodes. A second surface of the vibrating plate includes a plurality of groove regions extending radially, and the depths of the groove regions change in a circumferential direction along a curve obtained by superimposing one or more sine waves on one another. The ultrasonic motor exhibits a sufficient drive speed while suppressing generation of an unnecessary vibration wave.

Provided are an ultrasonic motor and a drive control system and the like using the ultrasonic motor. The ultrasonic motor includes an annular vibrator and an annular moving member arranged so as to be brought into pressure-contact with the vibrator. The vibrator includes an annular vibrating plate and an annular piezoelectric element. The piezoelectric element includes an annular piezoelectric ceramic piece, a common electrode arranged on one surface of the piezoelectric ceramic piece, and a plurality of electrodes arranged on the other surface of the piezoelectric ceramic piece. The piezoelectric ceramic piece contains lead in a content of less than 1,000 ppm. The plurality of electrodes include two drive phase electrodes, one or more non-drive phase electrodes, and one or more detection phase electrodes.