A multilayer electronic component having a plurality of laminated dielectric layers and inner electrode layers. The dielectric layers have a plurality of crystal grains including first regions where Re is dissolved in a solid state; and second regions where Re is not dissolved in the solid state. A median size of the crystal grains to an average thickness of the dielectric layers is 0.5≤t≤0.7. A ratio of a sum of cross sectional areas of the first regions to those of the plurality of crystal grains is 0.7≤s≤0.9. When a total amount of Ti, Zr, and Hf is 100 molar parts in the dielectric layers, a sum of the Zr and the Hf is 0≤a≤1.0; an amount b of Si is 0.1≤b≤1.0; an amount c of Re is 0.5≤c≤10.0; and a ratio m of a total of Ba and Re to a total of Ti, Zr, and Hf is 0.990≤m≤1.050.

A multilayer ceramic capacitor includes a multilayer structure having a substantially rectangular parallelepiped shape and including dielectric layers and internal electrode layers that are alternately stacked, the dielectric layers being mainly composed of BaTiO.sub.3, the internal electrode layers being alternately exposed to two edge faces of the multilayer chip opposite to each other. A Zr/Ti ratio is 0.02 or more and 0.10 or less in a capacity section. A Ba/Ti ratio is more than 0.900 and less than 1.010 in the capacity section. A Eu/Ti ratio is 0.005 or more and 0.05 or less in the capacity section. A Mn/Ti ratio is 0.0005 or more and 0.05 or less in the capacity section. A total amount of a rare earth element or rare earth elements is less than the amount of Eu.

A piezoelectric composition having a complex oxide including potassium and niobium, in which the complex oxide has a first phase represented by a compositional formula KNbO.sub.3, and one or two phases selected from a second phase represented by a compositional formula K.sub.4Nb.sub.6O.sub.17 and a third phase represented by a compositional formula KNb.sub.3O.sub.8.

A multilayer capacitor includes a body including a plurality of dielectric layers, and a plurality of internal electrodes stacked with one of the dielectric layers interposed therebetween, and external electrodes disposed on external surfaces of the body and connected to the internal electrodes, respectively. The plurality of dielectric layers include a dielectric expressed by empirical formula BaM1.sub.aTi.sub.1-xSn.sub.xM2.sub.bO.sub.3 (0.008≤x≤0.05, 0.006≤a≤0.03, and 0.0006≤b ≤0.006) in which M1 includes a rare earth element, and M2 includes at least one of Mn or V.

A dielectric material includes a base material containing barium zirconate titanate as a main component, containing zirconium in an amount of 4 at % or more and 30 at % or less with respect to titanium and zirconium, and having an atomic concentration ratio of barium to titanium and zirconium of 1 or more and 1. 1 or less, and a subcomponent containing 2 at % or more and 4 at % or less of europium with respect to titanium of the barium zirconate titanate.

A piezoelectric ceramic composition is represented by a composition formula A.sub.xBO.sub.3 and includes potassium sodium niobate containing K and Na that account for 80% or more of an amount of A-site elements and containing Nb that accounts for 70% or more of an amount of B-site elements. The piezoelectric ceramic composition contains Ta and Fe at a B-site.

The present invention relates to a ceramic material for a multilayer capacitor. The ceramic material has a composition according to the following general formula:

Pb.sub.(y−1.5a−0.5b+c+0.5d−0.5e−f)Ca.sub.aA.sub.b(Zr.sub.1−xTi.sub.x).sub.(1−c−d−e−d)E.sub.cFe.sub.dNb.sub.eW.sub.fO.sub.3,

where
A is one or more of the group of Na, K and Ag;
E is one or more of the group of Cu, Ni, Hf, Si and Mn; and
0<a<0.14,
0.05≤x≤0.3,
0≤b≤0.12,
0<c≤0.12,
0≤d≤0.12,
0≤e≤0.12,
0≤f≤0.12,
0.9≤y≤1.5 and
0.001<b+c+d+e+f
applies.

Further, the invention includes a capacitor comprising the described ceramic material.

An oxide superconductor of an embodiment includes an oxide superconductor layer having a continuous Perovskite structure containing rare earth elements, barium (Ba), and copper (Cu). The rare earth elements contain a first element which is praseodymium (Pr), at least one second element selected from the group consisting of neodymium (Nd), samarium (Sm), europium (Eu), and gadolinium (Gd), at least one third element selected from the group consisting of yttrium (Y), terbium (Tb), dysprosium (Dy), and holmium (Ho), and at least one fourth element selected from the group consisting of erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu).

One aspect of the present invention is a multilayer ceramic capacitor including a plurality of dielectric layers composed of a dielectric ceramic containing grains whose main component is barium titanate having a core-shell structure made up of a core part and a shell part, and grains whose main component is calcium titanate having a core-shell structure made up of a core part and a shell part; and a plurality of internal electrodes stacked alternately with each of the plurality of dielectric layers.

An oxide superconductor of an embodiment includes an oxide superconductor layer having a continuous Perovskite structure including rare earth elements, barium (Ba), and copper (Cu). The rare earth elements include a first element which is praseodymium, at least one second element selected from the group consisting of neodymium, samarium, europium, and gadolinium, at least one third element selected from the group consisting of yttrium, terbium, dysprosium, and holmium, and at least one fourth element selected from the group consisting of erbium, thulium, ytterbium, and lutetium. When the number of atoms of the first element is N(PA), the number of atoms of the second element is N(SA), and the number of atoms of the fourth element is N(CA), 1.5×(N(PA)+N(SA))≤N(CA) or 2×(N(CA)−N(PA))≤N(SA) is satisfied.