-
Atsuo Kuniba, Yasuhiro Akutsu, Miki Wadati
1986 Volume 55 Issue 10 Pages
3285-3288
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
It is shown that (
r−1)-state restricted eight-vertex SOS model (8VSOS) by Andrews, Baxter and Forrester is equivalent to
q-state Potts model with
q=4·cos
2(π⁄
r) (
r=4, 5, 6…) at criticality. The equivalence follows from the Temperley-Lieb algebra shared by the models which is nothing but
C*-algebra
Aq,n defined by Jones in von Neumann algebra theory. This implies the correspondence of indices for subfactors of type II
1 factors and discrete series of Virasoro algebra which labels the universality classes of the 8VSOS models.
View full abstract
-
Hiroshi Kondoh, Mitsugu Matsushita
1986 Volume 55 Issue 10 Pages
3289-3292
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Diffusion-limited aggregation (DLA) model with anisotropic sticking probability
Ps is computer-simulated on two dimensional square lattice. The cluster grows from a seed particle at the origin in the positive
y area with the absorption-type boundary along
x-axis. The cluster is found to grow anisotropically as
R⁄⁄∼
Nν⁄⁄ and
R⊥∼
Nν⊥, where
R⊥ and
R⁄⁄ are the radii of gyration of the cluster along
x- and
y-axes, respectively, and
N is the particle number constituting the cluster. The two exponents are shown to become assymptotically ν
⁄⁄=2⁄3, ν
⊥=1⁄3 whenever the sticking anisotropy exists. It is also found that the present model is fairly consistent with Hack’s law of river networks, suggesting that it is a good candidate of a prototype model for the evolution of the river network.
View full abstract
-
Shunsuke Hara, Takeshi Ishihara, Nobuyuki Toshima
1986 Volume 55 Issue 10 Pages
3293-3294
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Adopting the spheroidal variables to describe the muon coordinates, variational calculations are carried out for the ground and the excited states of the homo-nuclear muonic hydrogen molecular ion (ppμ)
+ and its isotopes with total angular momentum
J=0 and 1. The best binding energies among those so far reported are obtained for several states.
View full abstract
-
Hideyuki Sato, Masahiro Fujii, Kiyoshi Yonemitsu, Yoshichika \={O}nuki ...
1986 Volume 55 Issue 10 Pages
3295-3298
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The current-voltage characteristics of point contact heterojunctions between Mo and the intermetallic compounds CeB
6, CeAl
2, CeCu
2Si
2 and CeCu
6 were investigated at liquid He temperatures. The dynamic resistance of these compounds shows a dip near zero bias voltage and large asymmetric bias voltage dependence. These behaviours are explained in terms of thermoelectric effects and resistivity due to local heating near the contact.
View full abstract
-
Arisato Kawabata
1986 Volume 55 Issue 10 Pages
3299-3300
Published: October 15, 1986
Released on J-STAGE: May 29, 2007
JOURNAL
RESTRICTED ACCESS
The magnetoresistance of p-type semiconductors is investigated on a two-band model assuming strong spin-orbit coupling. The value of the magnetoresistance is the same as that of single-band model, contrary to the result of Altshuler
et al., who predicted the reduction of the magnitude by a factor 2.
View full abstract
-
Hidenori Kubo, Tatsuichi Hamasaki, Mitsuho Tanimoto, Koichi Katsumata
1986 Volume 55 Issue 10 Pages
3301-3304
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Cl
35 NMR measurements are carried out at 1.7 K on a random mixture of quasi-two-dimensional ferro- and antiferromagnets Rb
2Mn
1−xCr
xCl
4 (
x=1.0, 0.9, 0.8). NMR spectra of
x=1.0 and 0.9 in zero applied field show that these compounds are ferromagnetic. In the re-entrant spin-glass state of
x=0.8 a satellite line is observed together with the main lines. It is pointed out from the analysis of the results that, in the re-entrant spin-glass state, the ferromagnetic moments coexist with the moments whose directions homogeneously distribute in the
c-plane, such as vortices.
View full abstract
-
Hidetoshi Nishimori
1986 Volume 55 Issue 10 Pages
3305-3307
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
We present an argument for the existence of a geometry-induced phase transition in the ±
J Ising model on an arbitrary lattice (
d≥2) with asymmetric probability of ferromagnetic and antiferromagnetic bonds. This transition manifests itself as a vertical phase boundary separating, possibly, a ferromagnetic and a non-ferromagnetic (paramagnetic or spin glass) phases.
View full abstract
-
Guang-rong Qin, Tatsuyuki Kawakubo
1986 Volume 55 Issue 10 Pages
3308-3311
Published: October 15, 1986
Released on J-STAGE: May 29, 2007
JOURNAL
RESTRICTED ACCESS
Behaviors of membrane excitation due to square pulse current and constant current stimulations were simulated by a current controlled negative resistance circuit model which shows low and high conductance depending on the intensity of stimulation. The simulation realized the all-or-none response to a pulse current stimulation and the variety of repetitive responses to a constant current stimulation.
View full abstract
-
Tohru Yoneyama
1986 Volume 55 Issue 10 Pages
3313-3320
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Interacting (Int) Benjamin-Ono (BO) equations, certain coupled nonlinear integro-differential equations, are results of an extension or a decoupling of the BO equation. By using new operators, the solutions
ui of Int BO equations are obtained starting from the exact
N-soliton solution of the original BO equation. Then by examining weighted mean of pole positions of
ui, very simple and clear-cut results are obtained: the center of gravity of
ui moves with constant speed etc. Two-soliton interaction profiles are shown. Also shown the direct relationship of the solution
u of the BO equation and the solution ψ
i′ of its inverse scattering transform.
View full abstract
-
Kazuo Hida
1986 Volume 55 Issue 10 Pages
3321-3325
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The effect of quantum random force on the damped motion of a soliton in the one dimensional sine-Gordon model is investigated by the numerical simulation using quantum Langevin equation. It is found that the mean square displacement of the center of the soliton depends on time
t as
Atα (0<α<1) where
A and α depend on the strength of dissipation. The qualitative feature of the result is also applicable to other more realistic soliton bearing systems such as spin chains or polymers.
View full abstract
-
Sumiyoshi Fujiki, Keisei Shutoh, Sakari Inawashiro, Yoshihiko Abe, Shi ...
1986 Volume 55 Issue 10 Pages
3326-3337
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The XY-nature of the Ising model on the triangular lattice with the antiferromagnetic nn and ferromagnetic nnn interactions is studied by Monte Carlo simulations. The order parameter is defined via the cell spin which represents a set of Ising variables in each frustrated unit cell. The finite size effects on the
xy- and
z-components of the order parameter are analyzed separately. The fluctuation of the absolute value of the order parameters is introduced as a generalized susceptibility. The successive phase transition feature with the Kosterlitz-Thouless-like phase is strongly confirmed. A non-universal character of the model is discussed.
View full abstract
-
Atsuo Kuniba, Yasuhiro Akutsu, Miki Wadati
1986 Volume 55 Issue 10 Pages
3338-3353
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
For any
k-state model among the Gordon-Generalization (GG) hierarchy (J. Phys. Soc. Jpn.
55 (1986) 1092 and 2166), a systematic procedure to obtain the parametrized Boltzmann weights is presented. An exact expression for the free energy of the general
k-state model in the GG hierarchy is explicitly given. The procedure is successfully applied to determine the parametrization for the 5-state model in the GG hierarchy. It is concluded that each
k-state model in the GG hierarchy is exactly solvable.
View full abstract
-
Masatoshi Imada, Minoru Takahashi
1986 Volume 55 Issue 10 Pages
3354-3361
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
A quantum transfer matrix method is proposed and examined. To obtain finite temperature properties, a small number of Monte Carlo samples for the trace summation is taken without the Monte Carlo sampling of the path integral. We introduce the method of a random orthonormal base in the Monte Carlo sampling. This makes it possible to investigate larger size systems than the exact diagonalization. An advantage of this method is that it does not have negative sign difficulty in the path integral as contrast to the usual quantum Monte Carlo method. A quantum molecular dynamics method is also proposed to investigate dynamical correlation functions.
View full abstract
-
A. Shakeel, H. Khushnood, M. Irfan, A. Ahmad, A. H. Naqvi, M. Shafi
1986 Volume 55 Issue 10 Pages
3362-3369
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
For examining the characteristics of clusters produced in 400 GeV p-N interactions, experimental data have been analysed in terms of the predictions of various theoretical models dealing with the interactions of peripheral nature. The results reveal that the leading particle effect is more pronounced in low multiplicity events. Furthermore, about 90% of the disintegrations having multiplicities in the interval 6
≤nch≤10 possess at least one cluster. Finally, on the basis of the study of short(long)-short(long) correlations, it is concluded that there might be several clusters present in an event and the cluster on an average decay into a minimum of three charged poins.
View full abstract
-
Yukio Yasuda, Noburu Sokabe, Akira Murai
1986 Volume 55 Issue 10 Pages
3370-3379
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Pulse-dye-laser-induced optogalvanic (OG) effect has been investigated on Hel(2
3S-3
3P) 388.9-nm in the positive column of a He glow discharge. It has been found that the peak OG current is approximately in proportion to the steady-state population difference between the 2
3S and 3
3P states. A rate equation analysis is made on the ion density and the population of the excited levels relevant to the optical pumping on the basis of the mechanism in which the excess charges responsible for the OG signal are generated and decay via associative ionization collision of the 3
3P state atoms optically pumped from the 2
3S state and via recombination governed by the ion wall current as described by Tonks and Langmuir, respectively.
View full abstract
-
Tohru Nakano
1986 Volume 55 Issue 10 Pages
3380-3387
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Scaling exponents associated with a passive scalar field in fully developed intermittent turbulence are examined on the basis of a new model, which was previously proposed for the intermittent velocity field, in addition to the lognormal- and β-models. Included are the exponents for the temperature structure function in the inertial-convective region, the moments of the volume-limited average scalar dissipation rate and the moments of the scalar field derivative. Those exponents are compared to the related data obtained by experiments.
View full abstract
-
Yutaka Shimomura
1986 Volume 55 Issue 10 Pages
3388-3401
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Two-scale direct-interaction approximation (TSDIA) is applied to the calculation of the turbulent passive scalar flux, the scalar variance, and the helicity in a rotating system. A skew-diffusion effect is confirmed to appear in a rotating system, which gives rise to the appearance of a component of turbulent scalar flux perpendicular to the local mean scalar gradient and to the axis of rotation. On this basis, the comparison between TSDIA and the smoothing theory is made, and an explicit form for the skew velocity in a rotating system is found.
View full abstract
-
Iwao Hosokawa, Shin-ichi Inage
1986 Volume 55 Issue 10 Pages
3402-3409
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
There are various types of bimodal approaches to the shock wave structure. How well the convection and the production of entropy (or the Boltzmann
H function) are locally balanced by these approaches through the shock wave in both hard and Maxwellian molecule gas, is investigated based on the Boltzmann transport equation for various upstream Mach numbers. The most successful bimodal approach is found from this point of view. A comparative discussion on other methods than bimodal is added.
View full abstract
-
Kazuo Minami, Koichi Izawa, Masanobu Kaminaga, Akira Ishida, Tsuguhiro ...
1986 Volume 55 Issue 10 Pages
3410-3418
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Theoretical analyses on the linear resonant absorption of electromagnetic waves in inhomogeneous plasmas given by various authors are re-examined by numerical computation. A set of linearized equations in which collisional and thermal effects of the electrons are included is solved numerically for a wide range of plasma parameters by developing an implicit difference scheme with extremely small numerical errors. We are successful to decrease electron temperatures as low as 200 K. It is concluded that the Denisov’s factor (
vt⁄\sqrt2ω
L)
2⁄3 with a numerical correction can be used to calculate the peak electrostatic fields at the resonant surface, if his factor is larger than 20 times the collisional factor ν⁄ω. Here,
L is the characteristic length of the density gradient and other notations are standard. An empirical formula to calculate the peak field in the presence of both collisional and thermal effects is proposed.
View full abstract
-
Akihiko Toda
1986 Volume 55 Issue 10 Pages
3419-3427
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
A model of growth of polymer single crystals is presented, taking account of the effect of impurity on secondary nucleation and growth process. The impurity on growth steps interrupts further crystallization of molecules on the steps. This effect gives rise to rounded lateral habits for single crystals of poly(ethylene oxide), branched polyethylene and linear polyethylene. A once folded chain stem on extended chain crystal surface as well as small branch and adsorbed solvent have the effect of impurity, respectively. The effect on the growth mode and lateral habit is analytically derived by kinetic equations. The results are applied to supercooling dependence of growth rate and lateral habit of polyethylene single crystals grown from poorer solvents.
View full abstract
-
Minoru Tanaka
1986 Volume 55 Issue 10 Pages
3428-3436
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The distribution of the Voronoi polyhedron is calculated with the use of the molecular dynamics method for the system of 864 argon atoms in the raidly quenched state near the liquid helium temperature and also in the F.C.C. crystalline states at elevated temperatures. The topological characteristics of the polyhedra in the rapidly quenched state of argon is found very similar to those calculated for rapidly quenched rubidium consistent to the similarity found in the pair and the triplet distribution functions between two systems. The Voronoi polyhedron in the F.C.C. crystalline states concentrates in a few special types of the face-indices and retains somewhat cubic symmetries naturally. The polyhedron network in a rapidly quenched monatomic system is shown different topologically from that in a hot crystal.
View full abstract
-
Shin’ichi Takeda, Sh\={u}zi Harada, Shigeru Tamaki, Yoshio Wased ...
1986 Volume 55 Issue 10 Pages
3437-3444
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The structure factors of liquid Ga at 50°C and liquid Tl at 315°C have been determined by neutron diffraction with sufficient accuracy and are compared with those by X-ray diffraction. A remarkable difference in these structure factors is clearly found around the first peak region, as well as a slight variation of the first peak position and it is apparently larger than the experimental errors, for both liquid metals. The ion-electron correlation function has been evaluated from this difference with the help of theoretical calculation of the electron-electron correlation function. By the Fourier transform of this function, the radial distribution function of valence electrons around ion has been calculated. The difference of electron distribution between the same valent IIIb-metals are also discussed.
View full abstract
-
Junichi Tamura, Yoshiaki Kogure, Yosio Hiki
1986 Volume 55 Issue 10 Pages
3445-3461
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The attenuation of megahertz ultrasound has been measured in single crystals of ice at higher temperatures. Specimen crystals were grown by the Bridgman method from purified water, and crystals doped with various ions were also used. An overdamped resonance peak of dislocation damping always appeared in decrement-vs-frequency, and the peak frequency was shifted by the temperature change and by the Na-ion doping. It was also found that the attenuation value increased very rapidly with large fluctuation when the temperature approached the melting point, and that the temperature dependence of attenuation was sensitive to the ion doping. Experimental data were consistently analyzed on the basis of the vibrating dislocation model with the following conclusions: Dislocations are pinned by impurity ions (Na
+) through an elastic interaction between the two kinds of defects; the damping constant for the dislocation vibration is of the order of 10
−4 cgs; the density of grown-in dislocations is around 10
6 cm
−2; the dislocation density rapidly increases as [1−(
T⁄
Tmelt)]
−1 near the melting temperature.
View full abstract
-
Masatoshi Imada
1986 Volume 55 Issue 10 Pages
3462-3468
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Effects of randomness in the strong coupling electron systems, where the real space pairings of electrons have an important contribution are investigated in (quasi-) one-dimensional systems. For weak randomness, it is discussed that the nature of the ground state of purely one-dimensional systems does not necessarily reflect the low temperature properties of three-dimensional systems with quasi-one-dimensional anisotropy. In particular, the commensurate charge density wave and superconducting long range order persist for weak randomness. In the bipolaronic or biexcitonic region, Monte Carlo results show that the charge density wave is more strongly suppressed by randomness than superconductivity. The suppression of the CDW phase by impurities allows superconductivity to occur in parameter regime which were in a CDW phase for a pure system.
View full abstract
-
Yoshiaki Kogure, Toshio Mugishima, Yosio Hiki
1986 Volume 55 Issue 10 Pages
3469-3478
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The pulse heating method has been developed for measuring the thermal diffusivity of solids at low temperatures. The experimental procedures were such that the front surface of a disk-shaped specimen was irradiated by a ruby-laser pulse (pulse width<1 msec), and the time variation of the temperature at the rear surface was detected by thin-film bolometers (sputtered gold film at higher temperatures and painted carbon film at lower temperatures) and was recorded by a sensitive high-speed electronic apparatus. The measurements were made at temperatures between 300 and 4.2 K, and the specimen used were polyethylene (60% crystallinity). The method to analyze the experimental data was precisely described. It was shown that the finite pulse-time effect could be ignored due to the short duration of the laser pulse, and that the consideration should be made on the heat loss from the specimen to its surroundings through the heat conduction, and also that an adequate choice of the bolometers was important especially at lower temperatures.
View full abstract
-
Yasunori Yanagisawa
1986 Volume 55 Issue 10 Pages
3479-3483
Published: October 15, 1986
Released on J-STAGE: May 29, 2007
JOURNAL
RESTRICTED ACCESS
Photodesorption from oxygen pre-adsorbed MgO surfaces was studied in the temperature range of 300–473 K by mass spectrometry as compared with thermally stimulated desorption. The O
2 photodesorption occurs by the ultraviolet excitation with the threshold energy of about 4.1 eV. The photodesorption rate decays as t
−n with n of about 0.6, and n is little dependent on sample temperatures. The photodesorption yield decreases near 370 K with increasing temperature and this result is attributed to the thermal decay of surface electron traps. The mechanism of photodesorption is discussed.
View full abstract
-
Mieko Takagi
1986 Volume 55 Issue 10 Pages
3484-3487
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Dependence of the phase transition temperatures on the thickness of films has been studied by a thermodynamic theory. The result shows that the depression of the transition temperature is inversely proportional to the thickness. Calculated values of the lowering of the melting points of gold are 6.5°C for 100 nm thickness and 65°C for 10 nm thickness.
View full abstract
-
Naoto Nagaosa
1986 Volume 55 Issue 10 Pages
3488-3497
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The phenomenological theory of the neutral-ionic transition in TTF-Chloranil is developed taking into account the thermal excitations of the domain walls on a chain and the three dimensional interchain interactions. The changes in various physical quantities around the transition point reflect the competition between these two effects. We mainly discuss the optical spectra which give the microscopic probes of the degree of charge transfer ρ at each molecule. The effect of a single impurity detected in the optical spectra is also discussed. Comparing with the experimental data in TTF-Chloranil, the following two conclusions are derived for this material. (1) The energy of the domain wall is small (of the order of room temperature). (2) The interchain interaction is weak effectively.
View full abstract
-
Takashi Takahashi, Nihal Gunasekara, Takasi Sagawa, Hiroyoshi Suematsu
1986 Volume 55 Issue 10 Pages
3498-3502
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Angle-resolved ultraviolet photoelectron spectroscopy has been performed for a C
8K single crystal. The dispersive π
*-band near the \ ilde
K point and the so-called
K 4s band around the
Γ point are experimentally identified. The experimentally determined band structure has been compared with two different band calculations to discuss the charge transfer in C
8K. The observed difference in the spectral feature of the ‘K 4s’ band between the experiment and the calculation are also discussed.
View full abstract
-
Takeo Takizawa, Kohji Kanbara
1986 Volume 55 Issue 10 Pages
3503-3515
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
To investigate the characteristics of traps in the single crystal of CdIn
2S
4, thermally stimulated currents (TSC) were measured in the temperature range from 90 to 300 K under various conditions such as varying light intensity, wavelength of light, heating speed and so on. The results were analysed in terms of a discrete-level-model, first developed by Haering and Adams. On the bases of the slow retrapping regime, least-square-curve-fittings were made and trap energies were obtaind as 0.04 and 0.09 eV for shallow traps and 0.23 eV for deep ones, other trapping aparameters also being obtained. Since structure due to deep traps was observed in TSC only by excitation at high temperature above 170 K, those traps were considered to have potential barriers around them as analogous to those observed in CdS by Bube
et al.
View full abstract
-
Katsuichi Tankei, Fumihiko Takano
1986 Volume 55 Issue 10 Pages
3516-3526
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The motion of electrons in the one-dimensional disordered system including
N δ=function potentials of random locations and strengths is studied by using the random transfer matrix method. The statistical properties of the electrical resistance ρ
N are discussed in the limit
N→∞. By studing the cumulant expansion of
fN=ln (1+ρ
N) in the cases when only the locations of potentials are random and the uniform strength is extremely small or large, it is found that the probability distribution of
fN is not normal in the large strength limit in contrast to the argument by Anderson
et al. and by Abrikosov. In the general case when both locations and strengths are random, the inverse localization length is numerically calculated under the assumption of the normal distribution of
fN.
View full abstract
-
Kozo Okada, Akio Kotani
1986 Volume 55 Issue 10 Pages
3527-3538
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The magnetization process in films of ferromagnetic superconductors is studied theoretically by concentrating mainly on the region near the lower critical field
Hc1. Below a characteristic temperature, where the magnetic interaction energy plays an important role, the following are predicted: the unusual dependence of
Hc1 on the film thickness, the discontinuity of the magnetization curve due to the change of the vortex lattice structure and the change of the transition type from II/1 to II/2 with decreasing the film thickness. The possibility of another type (II/3) of phase transition is also discussed. The mechanisms of these results are analyzed with particular attention to the roles of the interaction between each vortex and the magnetic field penetrating from the surface, the surface-affected intervortex interaction and the saturation effect of the magnetization which is mainly caused by the penetrating field.
View full abstract
-
Masatoshi Imada
1986 Volume 55 Issue 10 Pages
3539-3544
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Excited states in superconductors formed at normal impurities are investigated in the circumstance that the effective fermi energy is at most an order or magnitude larger than the superconducting gap and consequently the coherence length is roughly an order of magnitude larger than the lattice constant. It is discussed that the substantial spatial variation of the order parameter amplitude around an impurity easily occurs. The excitation energy of the bound state around the impurity extends down to a tenth of the gap in typical examples, which results in a new type of gapless-like behavior except at extremely low temperatures. The specific heat shows qualitatively different behavior from the BCS result and does not follow simple temperature dependence.
View full abstract
-
Toshio Itami, Kenji Shimokawa, Takayuki Sato, Mitsuo Shimoji
1986 Volume 55 Issue 10 Pages
3545-3552
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The molar magnetic susceptibility, χ
M of liquid Hg–Na and Hg–In alloys was measured from room temperature to 723 K using the Faraday method. The concentration dependence curve (CDC) of χ
M for liquid Hg–In alloys shows positive deviations from the linear law. The results of liquid Hg–Na alloys have a positively enhanced tendency in the intermediate concentration range, though the overall concentration dependence remains to be slightly negative (“W shape”); this type of CDC of χ
M is similar to that of liquid Hg–Cs alloys. Such a tendency of deviations has been discussed in terms of the nearly free electron theory for χ
M of liquid alloys. Maxima at a few at.% solute (In or Na) found in the CDC of the temperature coefficient of χ
M, dχ
M⁄d
T, appear to indicate an evidence of higher order correlation effects, as observed in many liquid Hg alloys.
View full abstract
-
Yoshinori Takahashi
1986 Volume 55 Issue 10 Pages
3553-3573
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The origin of the Curie-Weiss law of the magnetic susceptibility universally observed in ferromagnetic materials is discussed from a point of view that the local spin fluctuation amplitude is almost conserved. A fully consistent treatment is presented which can deal with both the ordered phase and the paramagnetic phase on an equal footing. In the case of weakly ferromagnetic limit, Rhodes-Wohlfarth plot is revised from a new stand point. In the ordered phase, observed systematic trends of magnetization curves are explained in connection with the nature of dynamical spin fluctuation spectra. Some new interesting relations among various magnetic data are derived and compared with experiments. Temperature dependence of magnetic susceptibilities of Fe and Ni is also discussed.
View full abstract
-
Yoshihide Kimishima, Hironobu Ikeda, Akio Furukawa, Hiroshi Nagano
1986 Volume 55 Issue 10 Pages
3574-3584
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The magnetic properties of insulating quasi-two-dimensional mixed ferromagentic (F) and antiferromagnetic (AF) system K
2Cu
cMn
1−cF
4 were studied by d.c. and a.c. magnetic susceptibility (χ) measurements, and phase diagram of this system was obtained. AF-region lies in the Cu concentration range of 0≤
c<0.5, and F region does in 0.8<
c≤1. In the intermediate range (0.5<
c<0.8), spin-glass behaviors were observed in a.c.χ and d.c.χ below 1 K. The relatively low spin-glass transition temperature was intepreted to result from the characteristic of quasi-two-dimensional nature of this system. The random-field effects were observed in the AF region, and
TN(
c)-,
Tc(
c)-lines were discussed in relation to the percolation theory and orbital ordering of Cu
2+ ions.
View full abstract
-
Kazuyoshi Yoshimura, Masayuki Shiga, Yoji Nakamura
1986 Volume 55 Issue 10 Pages
3585-3595
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
55Mn spin-echo NMR spectra of RMn
2 compounds (R=heavy rare-earth) and their external field dependence have been measured in their magnetically ordered states. From the analysis of the
55Mn hyperfine field, the Mn magnetic moments have been estimated as 2.6 and 2.5 μ
B for GdMn
2 and TbMn
2, respectively, whereas as almost zero for DyMn
2, ErMn
2 and TmMn
2. For DyMn
2, a weak second
55Mn NMR signal has been observed, indicating the Mn moment of 2.1 μ
B. Concludingly, the onset of the Mn moment is very sensitive to the interatomic spacing of Mn atoms in the RMn
2 system: a large spacing stabilizes a substantially large Mn moment, while a small spacing makes the Mn moment unstable.
View full abstract
-
Peter Böni, Gen Shirane, Boyce H. Grier, Yoshikazu Ishikawa
1986 Volume 55 Issue 10 Pages
3596-3604
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
We report the results of inelastic neutron scattering measurements on the ordered invar alloy Fe
3Pt in the paramagnetic phase. The qualitative properties of the magnetic scattering are similar to those measured in other isotropic cubic ferromagnets. We have found, however, that the temperature dependence of the quasielastic scattering is neither consistent with the predictions of Résibois and Piette for a Heisenberg ferromagnet, nor with band theory.
View full abstract
-
Seiji Miyashita
1986 Volume 55 Issue 10 Pages
3605-3617
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Magnetic properties of Ising-like Heisenberg antiferromagnets on the triangular lattice are studied. In particular, the magnetization curve,
Mz(
Hz), and phase diagrams in (
anisotropy,
Hz) are studied in the ground state, where
Hz is a magnetic field in an easy axis. Properties at finite temperatures are also studied, where four types of phases are found as well in the ground state. Non-trivial appearance of
xy-components of magnetization has been found at finite magnetic field
Hz. Difference between types of anisotropy, namely between a type with anisotropic coupling and a type with single-ion anisotropy, is also discussed.
View full abstract
-
Akira Mishima, Hiroshi Miyagi
1986 Volume 55 Issue 10 Pages
3618-3632
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The ortho-para mixture of solid H
2 is studied theoretically for fcc lattices of finite size, assuming EQQ interaction. The excitation spectrum is calculated by using the Hartree ground-state obtained numerically. The lowest excitation energy decreases with decrease of ortho concentration
X, and vanishes at
X∼0.55. The distribution of the local order parameters (LOP) is obtained in comparison with NMR line shape. Importance of the quantum effect is pointed out for the distribution of LOP which broadens rapidly with decrease of
X. The relaxation time
T1 is also studied as a function of NMR frequency shift, manifesting that ortho-H
2 with smaller value of order parameter relaxes more rapidly in the quadrupolar glass region.
View full abstract
-
Takanori Fukami, Shin Akahoshi, Kenzi Hukuda
1986 Volume 55 Issue 10 Pages
3633-3635
Published: October 15, 1986
Released on J-STAGE: May 29, 2007
JOURNAL
RESTRICTED ACCESS
The deuteration rates (D-rates) of H
2PO
4− radicals (
RP) in partially deuterated NH
4H
2PO
4 crystals are measured by ESR of SeO
43− doped in the crystals. It is found that the phase transition temperatures (
Tc) of the crystals depend linearly on
RP;
Tc(
RP)=148+94
RP [K]. Using this relation and data about total D-rate of highly deuterated ADP obtained by others, D-rates of NH
4+ radicals (
RN) in the crystals are calculated. It is pointed out that the shift of
Tc does not depend on
RN but on
RP.
View full abstract
-
Hirokazu Tsunetsugu, Eiichi Hanamura
1986 Volume 55 Issue 10 Pages
3636-3654
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Several nonlinear optical phenomena are described exactly for two-level electronic systems with a Gaussian frequency modulation under a pump field of arbitrary strength. We discuss the emission spectrum and the absorption spectrum of weak probe field under pumping in the frequency region, and the free induction decay (FID) and the optical nutation (ON) as examples of the coherent optical transients in the time region. It is shown that the relaxation behavior depends upon the pumping field intensity, i.e., the effect of the frequency modulations is reduced when the Rabi frequency increases beyond the amplitude or the inverse correlation time of the frequency modulation. We further show that the relaxation behavior depends upon the particular nonlinear optical phenomena, i.e., the vertex correction due to the frequency modulation works in the FID but does not in the ON.
View full abstract
-
Junji Nakatsuka, Masuo Fukui
1986 Volume 55 Issue 10 Pages
3655-3658
Published: October 15, 1986
Released on J-STAGE: May 29, 2007
JOURNAL
RESTRICTED ACCESS
Optical constants of fused quartz are determined from the dispersion analysis of attenuated total reflection (ATR) spectrum in the frequency range 300 cm
−1 to 1600 cm
−1. The ATR spectrum has been fitted with the theoretical one obtained by using the dielectric constant of fused quartz that is expressed by an eight-oscillator model.
View full abstract
-
Nobuhito Ohno, Kaizo Nakamura, Yoshio Nakai
1986 Volume 55 Issue 10 Pages
3659-3663
Published: October 15, 1986
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Reflection spectra of a single crystal of orthorhombic TlI have been measured for the polarization
E⁄⁄
c and
E⁄⁄
a over a range of photon energy from 2.6 to 4.1 eV at 2 K. The spectra show pronounced anisotropy between these polarizations. The lowest exciton transition at 2.87 eV is confirmed to occur in a cationic sublattice (Tl
+ 6
s→6
p). However, the admixture of the cation
s orbital in the top valence band is found to be not so large as in cubic thallous halides. The binding energy of the first exciton is estimated to be 17.1 meV.
View full abstract
-
Iwao Mogi, Norimichi Kojima, Toshiro Ban, Ikuji Tsujikawa
1986 Volume 55 Issue 10 Pages
3664-3670
Published: October 15, 1986
Released on J-STAGE: May 29, 2007
JOURNAL
RESTRICTED ACCESS
The magnetic field dependence of the absorption spectra corresponding to the transition
4T1(
4F)→
2T1(
2P) of Co
2+ in CsCoCl
3·2H
2O was investigated. In this transition region the Davydov splitting of the exciton lines was observed, and the magnitudes of the intersublattice exciton transfers were estimated. As a result, it was found that the exciton shows the two-dimensional migration closely related to the spin structure.
View full abstract
-
Tetsusuke Hayashi, Tokiko Ohata, Shigeharu Koshino
1986 Volume 55 Issue 10 Pages
3671-3682
Published: October 15, 1986
Released on J-STAGE: May 29, 2007
JOURNAL
RESTRICTED ACCESS
The decay of indirect exciton luminescence in CdI
2 crystals mixed with CdBr
2 has been measured following pulsed excitation at low temperatures. Three exponential decay components are observed. The intensity distribution among them varies with temperature as well as with Br
−-concentration. The time-resolved measurement of the emission spectra suggests that the emission of the slow decay component originates from a shallow bound state of an exciton located below the free state. The decay characteristics and the temperature dependence of the emission efficiency are accounted for in terms of changing populations in both the free and bound states. The result of analysis indicates that the potential barrier between the free and the self-trapped exciton states is lifted by the mixing of CdBr
2.
View full abstract
-
Masato Yoshimori, Kiyoaki Okudaira, Tomoki Yanagimachi
1986 Volume 55 Issue 10 Pages
3683-3688
Published: October 15, 1986
Released on J-STAGE: May 29, 2007
JOURNAL
RESTRICTED ACCESS
The Hinotori satellite observed an unusual time history of hard X-ray and gamma-ray emissions from a limb flare on 4 April, 1981. The detailed comparison of the time history reveals that the gamma-ray emission precedes the hard X-ray emission by about 10 s. Following three possibilities are suggested to explain the unusual time history: (1) The ion acceleration precedes the electron acceleration, (2) the ions and electrons are simultaneously accelerated, but the nuclear reactions responsible for gamma-ray emission precede the electron bremsstrahlung responsible for hard X-ray emission, and (3) the gamma-rays and hard X-rays are simultaneously emitted, but the hard X-rays are strongly attenuated from the limb effect.
View full abstract
-
Isao Yamada, Koji Ubukoshi, Kinshiro Hirakawa
1986 Volume 55 Issue 10 Pages
3689-3690
Published: October 15, 1986
Released on J-STAGE: May 29, 2007
JOURNAL
RESTRICTED ACCESS