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High-pressure AC-susceptibility measurement has been carried out in UIr. Three series of peaks corresponding to the successive ferromagnetic transitions indicate the existence of three ferromagnetic phases FM1-3. The phase boundary between FM2 and FM3 was not realized in the resistivity measurement. The Meissner effect is observed successfully in the pressure range of 2.63–2.74 GPa where the peak of AC-susceptibility survives. This result indicates that the superconducting phase is embedded in the FM3 phase with the ordered moment less than 0.05 μ B /U and adjoins the quantum critical point.

This study designed and developed a novel tactile display that provides a multi-push sensation by using a 6-axis motion platform. The display mechanically controls the position and orientation of a surface panel. A user touching an on-screen button with one finger can push the button vertically. When the user subsequently touches the display with a second finger, the surface panel declines and the position of the first finger remains unchanged. Thus, the user can push at two positions on the surface panel. We also developed a prototype system with six servomotors and a touch panel based on the principle of frustrated total internal reflection.

A new MHD (magnetohydrodynamics) generator based on electromotive force using seawater, that is, a helical-type seawater MHD generator with a 7 T solenoid superconducting magnet, is designed, constructed and tested. The constructed generator contains a helical insulation wall made of polyvinyl chloride 140 mm long and 100 mm in diameter, an anode rod made of SUS316 1350 mm long and 10 mm in diameter, and a cathode pipe made of SUS316 260 mm long and 100 mm in diameter. In the experiment, electromotive force and generator output are measured in terms of average flow velocity (0-5.6 m/s) and magnetic field (0-7 T) using artificial seawater (3.4% NaCl aqueous solution). As a result of the experiment, it was found that the electromotive force increases proportionally to average flow velocity and magnetic field, and that the generator output increases quadratically to average flow velocity and magnetic field over certain points. Experimental values are discussed by comparing the theoretical values and computed values.

Pressure-induced superconductivity is found in UIr without inversion symmetry. The pressure–temperature phase diagram has been investigated by means of the electrical resistivity and magnetization ...

A unique control method for a diverging seawater flow based on electromagnetic force, the so-called MHD (magnetohydrodynamics) separation method, is performed. The experimental apparatus is composed of a 10-T class superconducting magnet, a separation cell, a seawater tank, and a flow system. The constructed separation cell contains parallel electrodes, 18 mm wide, 40 mm long and 20 mm apart, and a diverging duct divided into equal parts, A (not affected by electromagnetic force) and B (affected by electromagnetic force). The dependence of flow ratio (mass of side-A sample solution/total mass of sample solution) on electric current, magnetic field, NaCl concentration and sample velocity has been studied experimentally using NaCl aqueous solution. The possibility of flow control of seawater with a diverging duct by the MHD separation method as well as experimental results are discussed.

We report the discovery of pressure-induced superconductivity in ferromagnetic UIr, which lacks inversion symmetry in the crystal structure. The Curie temperature TC1 = 46 K at ambient pressure decreases with increasing pressure, reaching a value of 11 K at 1.5 GPa. It presumably decreases further up to about Pc1 = 1.7 GPa. The ferromagnetic region named 'F1' exists up to Pc1. A second magnetic phase named 'F2' with a low ferromagnetic moment appears in the pressure range from 1.9 to 2.4 GPa. In the 'F2' phase, the magnetic transition temperature TC2 decreases with pressure, from 18 K at 1.9 GPa to approximately zero at PC2 = 2.6–2.7 GPa. In this critical pressure region, superconductivity appears below Tsc = 0.14 K.

The transport properties of the itinerant ferromagnet U3P4 have been studied at high pressures up to 6.0 GPa using a diamond anvil cell. The Curie temperature TC decreases with increasing pressure, but then TC cannot be assigned above 4.0 GPa. The coefficient A, assuming the Fermi liquid behavior (p(T) = p0 + AT2) at low temperatures, shows a maximum at 5.3 GPa. The temperature dependence of the resistivity at 5.0 GPa follows T5/3 which is expected in the SCR theory of a three dimensional ferromagnet. From these results, it is concluded that the ferromagnetic-nonmagnetic transition exists at around 5.0 GPa.

In order to investigate a relationship between the carrier concentration and negative magnetoresistance in the underdoped region, they have performed out-of-plane electrical resistivity measurements for underdoped Bi{sub 2}Sr{sub 1.6}La{sub 0.4}CuO{sub 6+{delta}} single crystals. Giant negative magnetoresistance has been observed in the most abundant carrier sample with {delta} = 0.12 in the experiment. The negative magnetoresistance reduces with decreasing carrier concentration.

UIr crystallizes in the monoclinic crystal structure without inversion symmetry. The magnetization measurement indicated that UIr is an Ising-type ferromagnet with the Curie temperature T C 1 = 46 K at ambient pressure. We grew a high-quality single crystal by the Czochralski method in a tetra-arc furnace. The ingot was annealed under high vacuum by the solid state electrotransport method. Superconductivity with a transition temperature T sc = 0.14 K was found under pressure.

Anisotropic resistivity in UIr has been investigated under high pressure. A huge enhancement of residual resistivity was found under high pressure for the measuring current parallel to the [0 1 0] direction while any anomalies were not observed in the resistivity for [1 0 1 ]. The residual resistivity for [0 1 0] reduced to the original value in the pressure range where superconductivity appears. This anomalous behavior indicates that the ground state in the high-ρ 0 state is not simple ferromagnet and the application of pressure induces the first-order transition to slightly different electronic state.

Pressure-induced superconductivity is found in UIr without inversion symmetry. The pressure–temperature phase diagram has been investigated by means of electrical resistivity and magnetization. The phase diagram consists of two ferromagnetic phases. The ferromagnetic phase FM1 with T C 1 ∼ 46 K at ambient pressure disappears around 1.7 GPa. With further increase of pressure, the phase (FM2) with small ferromagnetic moment appears in the pressure range of P C 1 P 2.6 GPa . The superconducting phase exists near the disappearance point of the FM2 phase, indicating that the superconductivity is associated with the ferromagnetic critical fluctuation around P C 2 .

Strain and resistivity measurements in UIr showed the occurrence of two structural phase transitions under high pressure, indicating the existence of three phases I--III, with slightly different crystal structures. It is suggested that ferromagnetic phases FM1--FM3 emerge in phases I--III, respectively. The pressure-temperature phase diagram was sensitive to the hydrostaticity of pressure. FM3 and superconductivity are observed in the measurements in which Daphne 7373 is used as a pressure-transmitting medium; however they are both absent in the case where petroleum ether is used as a pressure-transmitting medium. These results indicate a close relationship between ferromagnetism and superconductivity.

We have investigated the dependence of superheat limit, TS, on the concentration of the liquid mixture of Ar and O2. TS has been carefully measured at atmospheric pressure by pulsed heating of a sample liquid on a 0.05‐mm‐thick platinum wire which doubles as a heater and a resistance thermometer. The experimental and theoretical TS values based on the conventional homogeneous nucleation theory are compared from the viewpoint of the dependence of TS of the liquid mixture on molar fraction. Results showed that there is a small difference between them: the experimental value is 0.8 K less than the theoretical value for a 50 mol% O2 sample; this difference exceeded the limit of measurement error. The cause of this difference is discussed.

Pressure-induced superconductivity is found in UIr without inversion symmetry. The pressure–temperature phase diagram has been investigated by means of the electrical resistivity, ac-susceptibility and magnetization measurements under high pressure. The phase diagram consists of three magnetic phases FM1–3 and a superconducting phase. The huge enhancement of residual resistivity and the negative magnetoresistance are found in the intermediate pressure region. These behavior may be induced by the pressure-induced structural phase transition and the accompanied phase separation in this pressure range. The superconducting phase with narrow pressure range is embedded in the FM3 phase, adjacent to zero-temperature FM3-to-nonmagnetic transition. The temperature dependence of resistivity above T SC follows non-Fermi liquid form of T 1.6 . From these experimental facts, superconductivity is considered to be associated with the ferromagnetic fluctuation.

We have studied the pressure–temperature phase diagrams in UIr, U3P4, UP2, CeAgSb2 and CeMg2Cu9 by means of the electrical resistivity. Application of pressure suppresses the magnetic ordering shown at ambient pressure in all compounds. In UIr, the pressure-induced superconductivity is observed in the vicinity of the magnetic–nonmagnetic transition. In this article, we review the pressure–temperature phase diagram and the properties of the magnetic–nonmagnetic transition in these compounds.

The antiferromagnet CeNiGe 3 exhibits superconductivity under pressure. The Neel temperature initially increases with increasing pressure up to 3 GPa and then becomes zero at a critical pressure ( ...