Abstract: A Faraday's rotator comprises a magnetic crystal which has a composition represented by the following compositional formula: (Tb.sub.1-(a+b+c+d) Ln.sup.1.sub.a Ln.sup.2.sub.b Bi.sub.c M.sup.1.sub.d).sub.3 (Fe.sub.1-e M.sup.2.sub.e).sub.5 O.sub.12, has a lattice constant of 12.383.+-.0.006 .ANG. and is grown through the liquid phase epitaxial growth technique. In the foregoing formula, Ln.sup.1 is at least one element selected from the group consisting of Yb, Lu and Tm; Ln.sup.2 is at least one member selected from the group consisting of rare earth elements except for Yb, Lu, Tm and Tb; M.sup.1 is at least one element selected from the group consisting of Ca, Mg and Sr; M.sup.2 is at least one element selected from the group consisting of Al, Ga, Ti, Si and Ge; 0.2.ltoreq.a.ltoreq.0.6, 0.ltoreq.b.ltoreq.0.3, 0 <c.ltoreq.0.16, 0<d.ltoreq.0.02 and 0<e.ltoreq.0.1. Another Faraday's rotator comprises a magnetic crystal having a composition represented by the following compositional formula: (Tb.sub.

Abstract: Proposed is a novel rare earth oxide-based magnetic garnet single crystal in the form of a film epitaxially grown in the crystallographic direction of <111> on the substrate of a rare earth oxide-based garnet single crystal, which is useful as a magnetostatic device such as high-frequency oscillators capable of exhibiting improved temperature characteristics. The magnetic garnet single crystal is characterized by the specific chemical composition of the formula (Bi.sub.x R.sub.3-x)(Fe.sub.5-y M.sub.y)O.sub.12, in which R, is a rare earth element selected from the group consisting of Y, Lu, La or a combination thereof, M is Ga, Al or a combination thereof, x is 0.02 to 0.4 and y is 0.6 to 0.8, and also by the specific value of the growth-induced magnetic anisotropy constant Ku.sup.g in the range from 0.3.times.10.sup.4 to 1.5.times.10.sup.4 erg/cm.sup.3 in the crystallographic <111> direction which can be imparted by an annealing heat treatment at a specified temperature.

Abstract: An optical isolator comprises a polarizer, a Faraday rotator, an analyzer and a magnet for applying a magnetic field to the Faraday rotator wherein the polarizer is incorporated into a first metal cylinder to form a polarizer unit, the Faraday rotator is incorporated into a cylindrical magnet to form a Faraday rotator unit and the analyzer is incorporated into a second metal cylinder to form an analyzer unit, the polarizer, Faraday rotator and analyzer units being arranged within an outer cylinder and the first metal cylinder and the second metal cylinder being joined to the outer cylinder through an adhesive component. The optical isolator can easily be produced, the adhered and supported portion thereof is not peeled off and it has high reliability.

Abstract: A novel oxide garnet single crystal, which can be epitaxially grown on a rare earth-gallium garnet wafer and exhibiting excellent performance as a material of magneto-optical devices, is disclosed. The oxide garnet single crystal, grown on the substrate surface by the liquid-phase epitaxial method, has a chemical composition expressed by the formula(Bi.sub.a Eu.sub.b Ln.sub.1-a-b).sub.3 (Fe.sub.1-c M.sub.c).sub.5 O.sub.12,in which Ln is a rare earth element other than europium, e.g., terbium, M is an element selected from the group consisting of aluminum, gallium, indium and scandium, the subscript a is a positive number defined by 0.15.ltoreq.a.ltoreq.0.6, the subscript b is a positive number defined by 0.01.ltoreq.b.ltoreq.0.2 and the subscript c is a positive number defined by 0.01.ltoreq.c..ltoreq.0.1.

Abstract: The radiation detector of the present invention comprises a joined scintillator block body which is composed of a plurality of photomultiplier tubes combined together and a plurality of scintillator blocks which are joined to entrance windows of the combined photomultiplier tubes so that the size of the entrance windows is in agreement with that of the light-outgoing plane of the scintillator blocks, the number of the scintillator blocks being greater than that of the photomultiplier tubes. The joined scintillator block body is designed such that the reflectances of the interfaces between the scintillator blocks increase as they are positioned away from the interfaces of the combined photomultiplier tubes.

Abstract: The joined scintillator block body for radiation detector according to the present invention comprises a plurality of scintillator blocks, each being divided into small scintillator chips through deep grooves formed by cutting each block from the light-incident side and filled with a reflecting material and these plurality of blocks being joined together, wherein a part of the joined faces of each neighboring two blocks is joined with the reflecting material and the remaining portion thereof is joined with a transparent resin layer capable of transmitting scintillation light rays emitted by the scintillator chips. In the foregoing joined scintillator block body for radiation detector, all of the divisions or scintillator chips of the joined scintillator block body have the same ability of light emission and, therefore, the radiation can always be detected at any portion on the photomultiplier tube under the sam conditions.

Abstract: The optical isolator of the present invention comprises a polarizer, a Farady rotator and an analyzer arranged in this order, wherein the Farady rotator has a garnet crystalline structure represented by the formula (Tb.sub.1-(a+b) Ln.sub.a Bi.sub.b).sub.3 (Fe.sub.1-c M.sub.c).sub.5 O.sub.12 wherein Ln represents at least one element selected from the group consisting of rare earth elements other than Tb; 0<a.ltoreq.0.6; 0<b .ltoreq.0.2; M represents at least one element selected from the group consisting of Al and Ga; and 0.ltoreq.c<0.1; or the formula (Tb.sub.1-(d+e+b) Ln.sub.d Eu.sub.e Bi.sub.b).sub.3 (Fe.sub.1-c M.sub.c).sub.5 O.sub.12 wherein Ln represents at least one element selected from the group consisting of rare earth elements other than Tb and Eu; 0<d<0.6; 0<e.ltoreq.0.2; 0<d+e.ltoreq.0.6; 0<b.ltoreq.0.2; M represents at least one element selected from the group consisting of Al and Ga; and O.ltoreq.C<0.1; or the formula (Y.sub.1-(a+b) Ln.sub.a Bi.sub.b).sub.3 (Fe.sub.

Abstract: A proposal is made for a magnetostatic-wave chip capable of treating a relatively large electric power even when the size of the magnetostatic-wave device, such as filters, delay lines, resonators and oscillators, constructed therewith is very small. The chip is prepared by the epitaxial growth of a rare earth-iron garnet film on the substrate surface and the desired performance of the device can be achieved when the parameters of .DELTA.H/4.pi.Ms,.DELTA.H being the half-value width of the magnetic rosonance peak at 9.2 GHz and 4.pi.Ms being the saturation magnetization, and the volume of the magnetostatic-wave film of the chip fall within the area defined by the five points P1 to P5 shown in FIG. 1.

Abstract: A novel oxide garnet single crystal, which can be epitaxially grown on a rare earth-gallium garnet wafer and exhibiting excellent performance as a material of magneto-optical devices, is disclosed. The oxide garnet single crystal, grown on the substrate surface by the liquid-phase epitaxial method, has a chemical composition expressed by the formula(Bi.sub.a Eu.sub.b Ln.sub.1-a-b).sub.3 (Fe.sub.1-c M.sub.c).sub.5 O.sub.12,in which Ln is a rare earth element other europium, e.g. terbium, M is an element selected from the group consisting of aluminum, gallium, indium, and scandium, the subscript a is a positive number defined by 0.15.ltoreq.a.ltoreq.0.6, the subscript b is a positive number defined by 0.01.ltoreq.b.ltoreq.0.2 and the subscript c is a positive number defined by 0.01.ltoreq.c..ltoreq.0.1.

Abstract: An optical isolator according to the present invention comprises a first polarizer, a Faraday rotator and a second polarizer which are adhered to one another in this order and held in a cylindrical magnet, wherein at least one adhered and supported portion comprises a low melting point glass 7 and 8. As the low melting point glass 7, 8, there may be used, for instance, those mainly comprising lead oxide and boron oxide; zinc oxide, lead oxide and boron oxide; lead oxide, boron oxide and thallium oxide; phosphoric acid and aluminum oxide; zinc oxide and boron oxide; and phosphorous pentaoxide, aluminum oxide and boron oxide. In the optical isolator according to the present invention, a low melting point glass is used for adhering the structural parts for the optical isolator, there is not observed any outgassing phenomenon due to the raise in ambient temperature as in the isolator which is assembled with an adhesive and the discrepancy of the optical axis due to the expansion of the adhesive.

Abstract: By a radiation detector comprising a photomultiplier tube, a Bi.sub.4 Ge.sub.3 O.sub.12 crystal of which a face contacted to the photomultiplier tube and reflecting layers which essentially consisting of reflecting powdery agent and an acrylic resin type binder provided on faces other than the face of the crystal, the energy resolution can be made smaller and stable. Thus, the resolution of the detector can be made higher. The detection accuracy can be improved since the energy resolution caused to be reduced and stabilized by raising the thickness of reflecting layers up to 50 .mu.m or more. Furthermore use of an acrylic resin, as a binder for forming the reflecting layers, is effective in eliminating the influence of the silicone-based adhesive agent, which allows to enhance the reflectance and adhesion of the reflecting layers. At the same time, a processing once suffices to build the reflecting layers thus resolving the problem of intricate manufacturing.

Abstract: An improved epitaxial single crystal wafer suitable as a working element of magnetostatic wave devices is proposed which comprises a substrate single crystal wafer of a rare earth gallium garnet, e.g., gadolinium gallium garnet, neodymium gallium garnet and samarium gallium garnet, and an epitaxial layer formed thereon having a chemical composition, different from conventional yttrium iron garnet, Y.sub.3 Fe.sub.5 O.sub.12, of the formula(Y.sub.1-x M.sub.x).sub.a Fe.sub.8-a O.sub.12 or (Y.sub.1-x M.sub.x).sub.a (Fe.sub.1-Y Q.sub.y).sub.8-a O.sub.12,in which M is an element selected from the group consisting of bismuth, lanthanum, gadolinium and lutetium, the subscript a is a positive number in the range from 3.0 to 3.1, the subscript x is a positive number in the range from 0.01 to 0.9, Q is an element selected from the group consisting of aluminum, gallium, indium and scandium and the subscript y is a positive number in the range from 0.1 to 0.2.

Abstract: An improvement in the Czochralski single crystal growing of a rare earth-gallium garnet such as gadolinium gallium garnet according to which the single crystal boules of a relatively large diameter and outstandingly free from any crystal defects and inclusions are readily obtained. The improved method comprises keeping the melt of the oxide mixture formed in an iridium crucible for at least 15 hours in the molten state before crystal growing is started. It was also shown that addition of certain additive gases, e.g. water vapor, carbon dioxide and oxygen, to the gaseous atmosphere mainly composed of, for example, nitrogen, in which crystal growing was performed, in a limited proportion was effective to further improve the crystal quality and to decrease the particulate inclusions in the single crystal boules.