Magneto-Acoustic Resonances in Antimony

Spike-like sharp absorption peaks have been observed in an ultrasonic attenuation coefficient of antimony in a weak magnetic field range. This type of resonance is not caused by the electron in an extremal orbit as has been observed in many cases of geometric resonance, but it is probably due to the particular kind of selective coupling predicted by Kaner et al. On applying the Kaner\u27s formula, we can get the cyclotron mass which is in agreement with the value derived from the Shoenberg\u27s results within 13 per cent

Electrical Properties of Amorphous Cu-Zr Alloy

The electrical resistivity of amorphous Cu_-Zr_ alloy and the temperature coefficient of the resistivity are estimated to be 195μΩ・cm and -1.23×10^μΩ・cm/°K at 273°K, respectively. The Hall coefficient and the thermoelectric power are equal to +7.4×10^ m^3/AS and +0.39μV/°K, respectively. These electrical properties are similar to those for some liquid transition metals

Hall coefficient of La1.88−y_{1.88-y}Yy_ySr0.12_{0.12}CuO4_4 (y=0,0.04y=0, 0.04) at low temperatures under high magnetic fields

The Hall coefficient in the low-temperature tetragonal phase and the mid-temperature orthorhombic phase of La$_{1.88-y}$Y$_y$Sr$_{0.12}$CuO$_4$ ($y=0, 0.04$) single crystals is measured under high magnetic fields up to 9 T in order to investigate the detailed behavior of the transport properties at low temperatures in the stripe phase. When the superconductivity is suppressed by high magnetic fields, the Hall coefficient has negative values in low temperatures, and the temperature region of the negative values spreads as increasing magnetic fields. This result indicates that the Hall coefficient in the stripe phase around $x=0.12$ is a finite negative value, not zero.Comment: 4 pages, 4 figures. to be published to Physical Review

Glykogenie der Leber beim Hungern unter Einfluβ von Insulin und Gallensaure.

1. Die Glykogenbildung der Leber von 4 Tage u. 7 Tage hungernden Kaninchen wird sowohl durch perorale Zufuhr von Cholsaure als auch durch subcutane Zufuhr von Insulin stark gesteigert. 2. Diese gesteigerte Glykogenbildung der Leber fastender Kaninchen tritt bei Zufuhr von Insulin viel starker auf, als bei Zufuhr von Cholsaure und diese Wirkung der beiden wird nach langerem Hunger wieder herabgesetzt.</p

Ground State at Low Landau Level Filling Factors in Two-Dimensional Systems of GaAs/AlGaAs Heterostructures in Strong Magnetic Fields(Research in High Magnetic Fields)

Integer and fractional quantum Hall effects are interesting phenomena in two-dimensional electron systems (2DES) in strong magnetic fields. In this paper, breakdown of the integer quantum Hall effect (IQHE) at odd integer filling factors at 100 mK and temperature dependence of the fractional quantum Hall effect (FQHE) around the filling facor ν=1/2 at temperatures between 100 mK and 1000 mK in magnetic fields up to 25 T are measured for the 2DES in two AlGaAs/GaAs heterostructures. The results in the IQHE measurements are compared with results at the even filling factors and derive the effective g-factor of about 10 in this system. The results in the FQHE measurements at ν=1/2 shows a logarithmic temperature dependence of the conductivity which is expected in a weakly localized Fermion system in zero magnetic fields

Low Temperature Ground States and Field-Induced Phase Transitions in α-(BEDT-TTF)_2-MHg(XCN)_4 (M=K, Tl, Rb, NH_4; X=S, Se) (Research in High Magnetic Fields)

There have been observed in a series of isostructural α-(BEDT-TTF)_2MHg(XCN)_4\u27s a variety of ground states such as spin-density-wave metallic state (M=K, Tl, Rb; X=S), superconducting one (M=NH_4; X=S), and simple metallic one (M=K, Tl; X=Se). Current status of these researches is outlined, including the magnetic field effects on the first group which appear in high fields more than 20T at low temperatures

Nonlinear Photomagnetoelectric (PME) Effect in Bi by Laser Irradiation

The transverse (nonoscillatory) and longitudinal (oscillatory) photomagnetoelectric effects have been measured with single crystals of Bi under pulsed illumination by a Q-switched Nd-laser (wavelenghth : 1.06μ) with its peak intensity range from 10^3 to 10^6 W/cm.^2 The superlinearity in the PME voltage is observed for the Faraday configuration for the beam intensity above 1.4×10^5 W/cm.^

NMR Study on La and Tl-based High-T_c Cuprates (High Field Superconductors)

NMR study on three types of high-T_C cuprates TlBa_2CaCu_2O_ (Tl1212), La_Ba_xCuO_4 (LBCO) and (La_Y_y)_Ce_xCuO_4 (LYCCO) is reported. First the Knight shift in the superconducting state was investigated for the Zn-substituted TlBa_2Ca(Cu_Zn_z)_2O_, which belongs to the over-doped region. The temperature dependence of the Knight shift was successfully explained in terms of the partially closed d-wave model proposed by Kitaoka et al. The reduction in T_C by Zn-substitution was also consistent with Miyake\u27s theoretical calculation on the potential scattering of the unitarity limit in the d-wave superconductors. Next, the impurity effect on the anomalous suppression of the superconductivity in La_Ba_xCuO_4 (LBCO) around x≅1/8 was investigated by La-NMR and ultrasonic measurements. The transition temperatures of the magnetic order and of the structural phase transformation in Zn^ and Ce^-doped LBCO have shown that the main and direct force to the suppression in the superconductivity is the magnetic ordering, and that the role of the structural phase transformation is the enhancement of the suppression. Lastly, the new electron doped cuprate free from 4f-spins has been synthesized and studied by NMR. Observed spectra of ^Cu without quadrupolar splitting similar to other conventional electron-doped cuprates indicate that the doped carrier in this system is electron like

Anomalous broadening of the spin-flop transition in the reentrant spin-glass phase of La2−x_{2-x}Srx_xCuO4_4 (x=0.018x=0.018)

The magnetization in a lightly doped La$_{2-x}$Sr$_x$CuO$_4$ ($x=0.018$) single crystal was measured. Spin-flop transition was clearly observed in the hole doped antiferromagnetically ordered state under increasing magnetic fields perpendicular to the CuO$_2$ plane. In the spin-glass phase below 25K, the spin-flop transition becomes broad but the step in the magnetization curve associated with the transition remains finite at the lowest temperature. We show in this report that, at low temperature, the homogeneous antiferromagnetic order is disturbed by the re-distribution of holes, and that the spatial variance of the local hole concentration around $x=0.018$ increases.Comment: to be published to Physical Review