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Focuses on a study which regarded a magnetic inverse problem as a spatial optimum allocation problem and adopted a Hopfield neural network is adopted to solve the optimization problem. Solution of initial state problem of Hopfield network using a genetic algorithm; Application of Hopfield neural network and genetic algorithm to the reconstruction of current distribution from magnetic fields; Analysis of computational simulations.

Deals with a study that investigated the magneto-optical (MO) properties of barium-ferrite particulate media. Measurement of Faraday rotation and reflexivity; Dependence of the MO output on thickness; Comparison of the dependence of the MO output on thickness with the predictions of analytic expressions approximating the Faraday rotation and the reflexivity.

Presents information on a study which measured the magnetic anisotropy constant of barium-ferrite platelet particles using torque magnetometer. Characteristics of barium-ferrite particles; Experimental procedure; Results and discussion; Conclusions.

Provides information on a study that applied the Mössbauer techniques on two types of tapes to evaluate the orientation of particles in magnetic recording tapes. Details on the experimental procedure; Results and discussion; Conclusions.

Investigates the magneto-optical readout properties of barium (Ba)-ferrite particulate media recorded by a magnetic head. Information on the Ba-ferrite particulate media; Discussion of the origin of noise in connection with the domain patterns observed using the polarized microscope; Comparison between the detection of clear images in particulate media and thin-film media.

Presents a study that examined the adsorption behavior of organic titanate on an iron foil having an ideal iron oxide surface to improve read-write characteristics of particulate magnetic recording media by the surface treatment of iron oxide magnetic particles with organic titanate. Effect of titanate on the surface hydrophilicity of oxide surface of the iron foil; Formation of the chemical bonding between the titanate and the oxide; Application of the method to cobalt-modified oxide.

To characterize the temporal evolution of ultrashort X-ray pulses emitted by laser plasmas using a pump-probe method, a magnetic bottle time-of-flight electron spectrometer is constructed. The design is determined by numerical calculations of a mirror magnetic field and of the electron trajectory in a flight tube. The performance of the spectrometer is characterized by measuring the electron spectra of xenon atoms irradiated with a laser-driven plasma X-ray pulse. In addition, two-color above-threshold ionization (ATI) experiment is conducted for measurement of the X-ray laser pulse duration, in which xenon atoms are simultaneously irradiated with an X-ray laser pump and an IR laser probe. The correlation in the intensity of the sideband spectra of the 4d inner-shell photoelectrons and in the time delay of the two laser pulses yields an X-ray pulse width of 5.7 ps, in good agreement with the value obtained using an X-ray streak camera. [ABSTRACT FROM AUTHOR]

Electric and magnetic characteristics of a Co-Fe-Si-B-based amorphous thin wire with a diameter of 120 μm were investigated at low temperatures from an applicative point of view. The electric resistivity decreases with the decrease of temperature and has the minimum point at about 30 K. The maximum decrease of the resistivity is, however, only 2.7% as compared with that at room temperature. The magnetic characteristics in term of the coercive force, the saturation induction, and the maximum permeability are all increased with the decrease of temperature. The coercive force shows the increase of 25% at 4.4 K as compared with that at room temperature; and the saturation induction and the maximum permeability about 15%. The very slight decrease of electric resistivity and the increase of the coercive force with the decrease of temperature promise a high-frequency application of the wire at low temperature. These results led to the fabrication of a multivibrator-type magnetometer being able to work at low temperature below 77 K. The magnetometer has a sensitivity of about 1 mV/mG at room temperature in a magnetic field range between + 1 and -1 Oe. The sensitivity change is less than 0.5% even at low temperature of 6 K, as compared with that at room temperature. [ABSTRACT FROM AUTHOR]

Ablation of LiF crystal by soft x-ray laser (XRL) pulses with wavelength λ=13.9 nm and duration TL=7 ps is studied experimentally and theoretically. It is found that a crater appears on a surface of LiF for XRL fluence, exceeding the ablation threshold Fa∼10.2 mJ/cm2 in one shot, or 5 mJ/cm2 in each of the three XRL shots. This is substantially below the ablation thresholds obtained with other lasers having longer pulse duration and/or longer wavelength. A mechanism of thermomechanical ablation in large bandgap dielectrics is proposed. The theory explains the low Fa via small attenuation depth, absence of light reflection, and electron heat conductivity. [ABSTRACT FROM AUTHOR]

We developed a new soft x-ray speckle intensity correlation spectroscopy system by use of a single shot high brilliant plasma soft x-ray laser. The plasma soft x-ray laser is characterized by several picoseconds in pulse width, more than 90% special coherence, and 10(11) soft x-ray photons within a single pulse. We developed a Michelson type delay pulse generator using a soft x-ray beam splitter to measure the intensity correlation of x-ray speckles from materials and succeeded in generating double coherent x-ray pulses with picosecond delay times. Moreover, we employed a high-speed soft x-ray streak camera for the picosecond time-resolved measurement of x-ray speckles caused by double coherent x-ray pulse illumination. We performed the x-ray speckle intensity correlation measurements for probing the relaxation phenomena of polarizations in polarization clusters in the paraelectric phase of the ferroelectric material BaTiO(3) near its Curie temperature and verified its performance.