Abstract: A magnetic recording medium for longitudinal recording with a low media noise, a high S/N ratio and high reliabilities in corrosion resistance is disclosed. By making a magnetic layer from a Co-based alloy comprising 1 to 35 at. % of at least one element selected from the group consisting of Pt and Ir, 1 to 17 at. % of at least one element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Ge and Si, except for Si, whose concentration is 1 to 40 at. %, and 0.1 to 10 at. % of oxygen, a magnetic recording medium for longitudinal recording having an inplane coercivity of 1,200 Oe or more and a coercive squares of not more than 0.85 is obtained.

Abstract: A superconducting device low in power dissipation and high in operating speed is fabricated by use of a combination of a superconductor material and a semiconductor material. The superconducting device having a low power dissipation and high operating speed characteristic according to the present invention is suitable for configuring a large-scale integrated circuit.

Abstract: Disclosed herein is a superconducting field effect transistor (FET) which has at least an active region formed from a film of oxide normal conductor, a plurality of electrodes formed from a film of oxide superconductor, and a means to control the current which flows between the electrodes through the active region. Having a much greater electrode distance than the conventional superconducting device, it can be produced easily by lithography without resorting to special techniques.

Abstract: Chemical reactions of superconducting raw materials with active oxygen atoms and their charged particles are accelerated by using at least oxygen plasma in the fabrication process of a superconductive body. Thereby an ionic crystal is grown in a short time, which provides stable superconducting materials of high quality such as high critical temperature and low resistivity. In another aspect, a substrate is irradiated simultaneously with streams of vapor of metal elements, of which a superconductive body is to be composed, and a stream of gas of ions generated in a plasma chamber and film growth is effected while keeping the substrate at a temperature higher than 400.degree. C. to produce a ceramic type superconductive thin film.

Abstract: A superconductive element at least comprising first and second superconductive electrodes composed of an oxide superconductor material and a semiconductor film composed of an oxide semiconductor material put between the first and second superconductive electrodes and disposed in adjacent with the first and the second superconductive electrodes, in which the semiconductor film is formed with an oxide comprising rare earth elements other than Pr, Ba and Cu as the main ingredient element or an oxide comprising predetermined amount of rare earth elements other than Pr, predetermined amount of Pr, Ba and Cu as the main ingredient element. Extremely fine size is no more necessary to enable fabrication with the existent fine fabrication technic.

Abstract: A magnetic recording medium that uses, as a protective coating layer provided on a magnetic layer for magnetically recording signals, a layer made of a nonmagnetic material consisting of two ore more elements of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W, and one or more elements of N, C, O, and B, or made of a magnetic material consisting of one or more elements of Co, Fe, Ni, and Gd, one or more elements of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W, and one or more elements of N, C, O, B, and Si is excellent in sliding endurance. When the protective coating layer is made of the nonmagnetic material, the magnetic recording medium is also excellent in corrosion resistance, and when the protective coating layer is made of the magnetic material, the spacing between a magnetic head and the magnetic recording medium can advantageously be made large. Both the cases are high in reliability, and suitable for high density magnetic recording.

Abstract: A ferromagnetic thin film of manganese and aluminum having varied atomic concentrations of manganese and aluminum in the direction perpendicular to the film plane, preferably the Mn atomic concentration being preferably in a range of 45 to 65% by atom, has a spontaneous magnetization equivalent to that of the bulk of manganese-aluminum alloy and also a high magnetic anisotropy.In addition, a magnetic recording medium comprises a substrate and a magnetic film formed on the substrate, the magnetic film being a thin film in a stacked structure of thin layers of manganese and thin layers of aluminum, laid open upon one another alternatingly in the film thickness direction.Finally, a manganese-silicon magnetic multi-layer film comprises thin layers of manganese and thin layers of silicon laid upon one another alternatingly.

Abstract: Disclosed are longitudinal recording media comprising a composite magnetic film formed on a nonmagnetic substrate directly or through a nonmagnetic underlayer, in which all of magnetic thin films constituting the composite magnetic film are magnetically connected, the composite magnetic film has a single in-plane coercivity, and the in-plane coercivity is greater than the in-plane coercivity of a longitudinal magnetically anisotropic magnetic thin film constituting a magnetic thin film nearest to an information recording side among the magnetic thin films constituting the composite film.

Abstract: A magnetic recording medium for longitudinal recording with a low media noise, a high S/N ratio and high reliabilities in corrosion resistance is disclosed. By making a magnetic layer from a Co-based alloy comprising 1 to 35 at. % of at least one element selected from the group consisting of Pt and Ir, 1 to 17 at. % of at least one element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W. Ge and Si, except for Si, whose concentration is 1 to 40 at. %, and 0.1 to 10 at. % of oxygen, a magnetic recording medium for longitudinal recording having an inplane coercivity of 1,200 Oe or more and a coercive squares of not more than 0.85 is obtained.A process for producing the magnetic recording medium for longitudinal medium and a magnetic memory apparatus using the magnetic recording medium for longitudinal recording are also disclosed.

Abstract: A process for controlling an oxygen content of a non-superconductive or superconductive oxide is provided, in which a beam of particles such as ions, electrons or neutrons or an electromagnetic radiation is applied to the non-superconductive or superconductive oxide of a perovskite type such as YBa.sub.2 Cu.sub.3 O.sub.7-x, thereby increasing or reducing the oxygen content of the oxide at the sites of oxygen in the crystal lattice of the oxide. Furthermore, a superconductive device such as a superconductive magnet, superconductive power transmission wire, superconductive transformer, superconductive shield, permanent current switch and electronic element is made by utilizing the process for controlling the oxygen concentration of the superconductive oxide.

Abstract: A weak-link Josephson junction is of the type employing a thin film of an oxide superconductor, in which a crystal grain boundary produced reflecting an artificial crystal defect is utilized as the weak-link junction. The crystal grain boundary is formed concretely by a method in which atoms of different species are deposited on the predetermined part of the surface of a substrate, the predetermined part of the surface of a substrate is disturbed, or parts of different crystal face orientations are formed at the surface of a substrate, whereupon the superconducting thin film is epitaxially grown on the substrate, or by a method in which the predetermined part of the superconducting thin film, epitaxially grown on a substrate, is diffused with atoms of different species hampering a superconductivity, or the predetermined part of the superconducting thin film is disturbed, whereupon the superconducting thin film is annealed.

Abstract: A process for fabricating a superconducting oxide thin film is disclosed which comprises the steps of separately evaporating metal elements, of which the superconducting oxide thin film with a desired stoichiometry is to be composed, to a substrate and simultaneously irradiating the substrate with oxygen plasma generated by RF wave or ECR microwave to form a crystalline oxide film without further annealing.

Abstract: Disclosed are a magnetic recording medium having a magnetic recording layer formed of a magnetic thin film in which rotational hysteresis integral R.sub.H is within a range of from 0.4 to 1.3 in the measurement by a torque magnetometer, and a continuous magnetic recording medium in which crystal grains are substantially randomly arranged on the upper surface of a magnetic recording layer or on the surface of a non-magnetic subbing layer, and in which each of the crystal grains is made to be in the form of an ellipsoid or needle and to have a length-ways axial ratio of a major axis to a minor axis not smaller than 2, more preferably, not smaller than 4.

Abstract: An oxide-superconductor improved so as to have a high critical temperature (T.sub.c) comprises an oxide having a K.sub.2 NiF.sub.4 crystalline structure similar to a perovskite crystalline structure and represented by the following formula:(Ba.sub.x Sr.sub.z La.sub.1-x-z).sub.2 Cu.sub.1-w Ag.sub.w O.sub.4(1-y)wherein 0.1<x+z<0.3, w=0, and y.gtoreq.0; or 0.ltoreq.x<1, 0.ltoreq.z<1, 0<w<1, and y.gtoreq.0. This invention also relates to an oxide-superconductor wherein an Na, K, Rb, Cs or F atom is contained in an oxide-superconductor of A.sub.3 Cu.sub.3 O.sub.7 type having at least one of a CuO.sub.6 octahedron and a CuO.sub.5 pentahedron.

Abstract: A magnetic recording medium in which a non-magnetic intermediate layer made of an alloy substantially composed of at least one element selected from the group consisting of Zr, Hf, Ta, Ti and Nb is disposed between a magnetic layer formed on a substrate and a non-magnetic overcoat layer formed on the magnetic layer. Since the impact shock resistance and the vibration resistance of the magnetic recording medium can be improved and the head-medium spacing of the magnetic disc apparatus can be decreased extremely by disposing the non-magnetic intermediate layer, it can provide a increase in the recording density, particularly, in a thin film type magnetic recording medium using a metallic magnetic thin film or metal oxide thin film as the magnetic layer. It can also improve the corrosion resistance in the case of a metallic magnetic thin film type medium.

Abstract: It is disclosed that a Heusler alloy thin film having a structure of a single crystal is prepared by forming a Heusler alloy thin film having a magneto-optical effect and an MgAgAs type crystalline structure on a single crystal substrate, whereby magnetization is easily effected in a low applied magnetic field. This single crystal thin film is suitable as a material of a head for writing magnetically and reading out optically.

Abstract: A magnetic recording medium having a magnetic film formed on a substrate directly or through an underlayer from an alloy containing Co as a principal component. The central line average surface roughness Ra and maximum surface roughness Rmax of the magnetic film in a direction perpendicular to the direction of magnetic recording are selected so as to fall within the ranges of 1 nm.ltoreq.Ra.ltoreq.20 nm and Rmax.ltoreq.25 Ra, respectively, and the in-plane magnetic anisotropy energy Ku of the magnetic film is selected to fall within the range of 0.ltoreq.Ku.ltoreq.8.times.10.sup.5 erg/cm.sup.3. Thus, it is possible to minimize the value of modulation which represents the degree of variation of read output on the same circumference of a magnetic disk. It is also possible to reduce the noise generated in read and write operations by forming the magnetic film so as have no crystallographic orientation.

Abstract: In a magnetic recording medium including an underlayer and a magnetic layer formed sequentially on a substrate, the underlayer is composed of a composite underlayer having an at least two-layered structure, the underlayer on the side of the substrate is made of a material providing low modulation to the magnetic recording medium while the underlayer on the side of the magnetic layer is made of a material providing a high S/N ratio to the medium. This makes it possible to obtain a magnetic recording medium having low modulation and high S/N ratio.

Abstract: There is provided a piezoelectric transducer comprising a substrate having a single crystal plate comprising strontium titanate or magnesium oxide, a first electrode comprising metal films so formed on the substrate as to leave openings exposing the surface of the substrate, a piezoelectric thin film comprising lead titanate as the main component formed so as to cover the openings and the first electrode, and a second electrode formed on the piezoelectric thin film.

Abstract: A closure lock system comprising a lock assembly, a lock actuator for locking or unlocking the lock assembly and a lock circuit including a reed switch which when closed by a magnet of a key causes the lock actuator to lock the lock assembly.