Abstract: A magneto-optic memory and a magnetic material is described incorporating a polarized light beam directed towards a magnetic material and an analyzer for intercepting the polarized light beam after passing through the magnetic material or after being reflected by the magnetic material. The magnetic material includes a matrix of metal such as iron, cobalt, nickel, and alloys thereof and a plurality of separated phases distributed in the matrix such as EuS, EuO, EuOTb, PtMnSb, MnAs, MnBi, MnSb, CrO.sub.2, CrTe, GdN, Gd.sub.4 C, other compounds of a rare earth element and manganese compounds. Terbium or neodymium may be dissolved in the matrix of metal and in the plurality of separated phases. The invention overcomes the problem of providing a magnetic material having a Curie point above room temperature, a square perpendicular hysteresis loop at room temperature, a large magneto-optic rotation at the wavelength of interest and a deposition temperature suitable depositing on polymer substrates.

Abstract: A magneto-optic memory and a magnetic material is described incorporating a polarized light beam directed towards a magnetic material and an analyzer for intercepting the polarized light beam after passing through the magnetic material or after being reflected by the magnetic material. The magnetic material includes a matrix of metal such as iron, cobalt, nickel, and alloys thereof and a plurality of separated phases distributed in the matrix such as EuS, EuO, EuOTb, PtMnSb, MnAs, MnBi, MnSb, CrO.sub.2, CrTe, GdN, Gd.sub.4 C, other compounds of a rare earth element and manganese compounds. Terbium or neodymium may be dissolved in the matrix of metal and in the plurality of separated phases. The invention overcomes the problem of providing a magnetic material having a Curie point above room temperature, a square perpendicular hysteresis loop at room temperature, a large magneto-optic rotation at the wavelength of interest and a deposition temperature suitable depositing on polymer substrates.

Abstract: An apparatus and method for imaging the magnetic structure and the magnetic domains of a sample is described incorporating a scanning tunneling microscope (STM), a voltage generator for varying the voltage on the tip, an ammeter for measuring the current through the tip, circuitry to determine the tip voltage at zero current and a current source for passing current longitudinally through the sample. The invention may further include an applied magnetic field in the plane of the sample and orthogonal to current passing through the sample. A high density non-volatile memory is described incorporating the above apparatus except for the applied magnetic field and further incorporating a layer of ferromagnetic material having magnetic domains therein indicative of information.