A relaxor-PT based piezoelectric crystal is disclosed, comprising the general formula of (Pb.sub.1-1.5xM.sub.x){[(M.sub.I,M.sub.II).sub.1-z(M.sub.I′,M.sub.II′).sub.z].sub.1-yTi.sub.y}O.sub.3, wherein: M is a rare earth cation; M.sub.I is selected from the group consisting of Mg.sup.2+, Zn.sup.2+, Yb.sup.3+, Sc.sup.3+, and In.sup.3+; M.sub.II is Nb.sup.5+; M.sub.I′ is selected from the group consisting of Mg.sup.2+, Zn.sup.2+, Yb.sup.3+, Sc.sup.3+, In.sup.3+, and Zr.sup.4; M.sub.II′ is Nb.sup.5+ or Zr.sup.4+; 0<x≤0.05; 0.02<y<0.7; and 0≤z≤1, provided that if either M.sub.I′ or M.sub.II′ is Zr.sup.4+, both M.sub.I′ and M.sub.II′ are Zr.sup.4+. A method for forming the relaxor-PT based piezoelectric crystal is disclosed, comprising pre-synthesizing precursor materials by calcining mixed oxides, mixing the precursor materials with single oxides and calcining to form a feeding material, and growing the relaxor-PT based piezoelectric crystal having the general formula of (Pb.sub.1-1.5xM.sub.x){[(M.sub.I,M.sub.II).sub.1-z(M.sub.I′,M.sub.II′).sub.z].sub.1-yTi.sub.y}O.sub.3 from the feeding material by a Bridgman method.

A layered portion includes, at least above an opening, a first single-crystal piezoelectric body layer, a second single-crystal piezoelectric body layer, an intermediate electrode layer, a lower electrode layer, and an upper electrode layer. The first single-crystal piezoelectric body layer includes a material that produces a difference in etching rate between a positive side and a negative side of a polarization charge. The polarization charge of the first single-crystal piezoelectric body layer is negative on a side of the intermediate electrode layer and positive on a side of the lower electrode layer.

Provided is an electric field-vibration generating transducer having a piezoelectric material of a high degree of displacement, and a manufacturing method thereof. The electric field-vibration generating transducer lowers the cost of production through miniaturization simultaneously with realizing excellent generating characteristics of the electric field-vibration generating transducer based on high efficiency and low voltage driving because the piezoelectric material of the high degree of displacement (high strain piezoelectrics) having a high piezoelectric constant (d.sub.33=1,000 to 6,000 pC/N), a high dielectric constant (K.sub.3.sup.T=6,000 to 15,000) as well as a low dielectric loss (tan δ<2%) is applied thereto, so the electric field-vibration generating transducer may accelerate the movement of a material, a chemical action, and a biological reaction, and may be applied to a medical device for the purpose of treatment for tumors aimed at human bodies and animals.

A tunable non-reciprocal frequency limiter with an asymmetric micro-electro-mechanical resonator has two independent transducer ports. One port has a film stack including a 10 nm hafnium zirconium oxide (HZO) and another port has a film stack including a 120 nm aluminum nitride (AlN) film. These film stacks are deposited on top of 70 nm single crystal silicon substrate applying CMOS compatible fabrication techniques. The asymmetric transducer architecture with dissimilar electromechanical coupling coefficients force the resonator into mechanical nonlinearity on actuation with transducer having larger coupling. A proof-of-concept electrically-coupled channel filter is demonstrated with two such asymmetric resonators at ˜253 MHz with individual Q.sub.res of ˜870 and a non-reciprocal transmission ratio (NTR) ˜16 dB and BW.sub.3 dB of 0.25%.

A piezoelectric device includes a piezoelectric body, a vibration plate that vibrates when the piezoelectric body is driven, a first electrode positioned between the piezoelectric body and the vibration plate, and a second electrode positioned to be separated from the first electrode by the piezoelectric body. The piezoelectric body has an active portion that is a part sandwiched between the first electrode and the second electrode in a first direction along a thickness direction of the piezoelectric body, and a change width of a dC/dV value, which represents a change in capacitance with respect to a change in a voltage applied along a second direction orthogonal to the first direction, from one end of the active portion on a side of the first electrode to the other end of the active portion on a side of the second electrode in the first direction is 10% or less.

A layered portion includes, at least above an opening, a first single-crystal piezoelectric body layer, a second single-crystal piezoelectric body layer, an intermediate electrode layer, a lower electrode layer, and an upper electrode layer. The first single-crystal piezoelectric body layer includes a material that produces a difference in etching rate between a positive side and a negative side of a polarization charge. The polarization charge of the first single-crystal piezoelectric body layer is positive on a side of the intermediate electrode layer and negative on a side of the lower electrode layer

Provided is an aluminum nitride film in which, aluminum nitride crystal grains containing a metal element differing from aluminum and substituting for aluminum are main crystal grains of a polycrystalline film formed of crystal grains, and a concentration of the metal element in a grain boundary between the aluminum nitride crystal grains in at least one region of first and second regions corresponding to both end portions of the polycrystalline film in a film thickness direction of the polycrystalline film is higher than a concentration of the metal element in a center region of the aluminum nitride crystal grain in the at least one region, and is higher than a concentration of the metal element in a grain boundary between the aluminum nitride crystal grains in a third region located between the first region and the second region in the film thickness direction of the polycrystalline film.

A polymer composite exhibiting piezoelectric properties can be formed for flexible and/or thin film applications, in which the polymer composite includes a polymer matrix and a piezoelectric ceramic filler embedded in the polymer matrix. The polymer matrix may include at least two polymers: a first polymer and a second polymer. The first polymer may be a fluorinated polymer, and the second polymer may be compatible with the first polymer and have a dielectric constant of less than approximately 20. The piezoelectric ceramic filler can be lithium doped potassium sodium niobite (KNLN), and be approximately 40-70% by volume of the polymer composite. The remaining 30-60% by volume may be the polymer matrix, which may itself be approximately 5-20% by weight second polymer and 80-95% fluorinated polymer.

The present application relates to an energy conversion apparatus. The energy conversion apparatus comprises: an upper conductive layer; a lower conductive layer, which is arranged below the upper conductive layer; and at least one piezoelectric micro/nano unit and a fluid, which are arranged between the upper conductive layer and the lower conductive layer, wherein the piezoelectric micro/nano unit has a piezoelectric property and is immersed in the fluid. The present application further relates to a preparation method for an energy conversion apparatus and the use thereof.

The present application relates to an energy conversion apparatus. The energy conversion apparatus comprises: an upper conductive layer; a lower conductive layer, which is arranged below the upper conductive layer; and at least one piezoelectric micro/nano unit and a fluid, which are arranged between the upper conductive layer and the lower conductive layer, wherein the piezoelectric micro/nano unit has a piezoelectric property and is immersed in the fluid. The present application further relates to a preparation method for an energy conversion apparatus and the use thereof.