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Susumu Chikazawa, Hideo Matsuyama, C. J. Sandberg, Yoshihito Miyako
1982 Volume 51 Issue 4 Pages
1037-1038
Published: April 15, 1982
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The field dependence of nonlinear susceptibility of (T
0.9V
0.1)
2O
3 was measured by ac-method. The nonlinear susceptibility increased logarithmically at
Tg as the amplitude
ho of ac-magnetic field was decreased from 20 Oe to 3 Oe. This behavior seems to be inconsistent with the results of dc-measurements and the prediction of mean field theory in the frame work of replica theory. This seems to suggest that dc-measurement is not the limit of ω→0 (non-ergotic system).
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Hiroshi Yasuoka, Claudio Jose Magon, Vincent Jaccarino
1982 Volume 51 Issue 4 Pages
1039-1040
Published: April 15, 1982
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NMR of
19F with no magnetic near neighbors (F
o) in the diluted antiferromagnet Mn
0.65Zn
0.35F
2 was used to study “random-field” effects on the critical behavior. From the temperature dependence of (1⁄
T1), for fields applied parallel and perpendicular to the easy (c) axis, it was found that the transition temperature
Tc depressed substantially with field only for
Ho||
c. The field dependence of Δ
Tc=
Tc⊥−
Tc|| is in general accord with the theory for random-field effects in disordered, anisotropic antiferromagnets, Δ
Tc∝
h2⁄φ, where
h=μ
Ho⁄
kTc. The value determined for the shift exponent φ=1.38±0.2 is in reasonable agreement with the prediction φ\simeq1.25.
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Yoshiro Akagi, Asako Kawamori, Hajime Kawamura
1982 Volume 51 Issue 4 Pages
1041-1042
Published: April 15, 1982
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ESR study of as-quenched and annealed Ge–S glasses was performed at various temperatures from 292 K to 408 K. The electron spin density in Ge
10S
90 is found to increase with temperature. At 408 K, which is just below the glass transition temperature (
Tg=423 k), it reaches twice as much as that at
T=292 K. The experimental facts together with a previous Raman result can be explained by a very short-chain crossing mechanism which arises from the instability of S–S bonds. In this model the ESR intensity can be regarded to reflect the medium range order of the glassy state. Observed annealing effects are also discussed.
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Kazuo Gesi
1982 Volume 51 Issue 4 Pages
1043-1044
Published: April 15, 1982
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Effect of hydrostatic pressure on the phase transitions in {N(CD
3)
4}
2ZnCl
4 was studied by dielectric measurements. The compound does not show ferroelectricity at 1 atm, but in a pressure range from 0.03 GPa to 0.13 GPa a ferroelectric phase appears. The pressure-temperature phase diagram of {N(CD
3)
4}
2ZnCl
4 is compatible with that found for other ferroelectric tetramethylammonium tetrachlorometallic compounds.
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Katsuhiko Hasebe, Hiroyuki Mashiyama, Sigetosi Tanisaki, Kazuo Gesi
1982 Volume 51 Issue 4 Pages
1045-1046
Published: April 15, 1982
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The superstructures were found in the low temperature phase of {N(CH
3)
4}
2CuBr
4. With decreasing temperature, the cell dimension changes as
b0, ∼2
b0, 2
b0 and
b0, respectively. The space group of each phase is Pmcn, incommensurate, Pbc2
1 and P12
1/c1. As the temperature decreases the modulation wave number
q0≈0.62
b* at −1°C decreases continuously to ∼0.57
b* at −31°C and jumps to the commensurate value of 1/2
b* in the ferroelectric phase.
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Kazuo Gesi, Masashi Iizumi
1982 Volume 51 Issue 4 Pages
1047-1048
Published: April 15, 1982
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Satellite reflections at (0, 2, ±δ) in SC(ND
2)
2 were measured by neutron diffraction with and without d. c. bias electric field
Eb in the vicinity of the ferroelectric III phase. At
Eb=0 the parameter δ continuously passes the value of 1/8 and clamping at 1/8 was not observed, while at
Eb=129 kV m
−1 it was clamped at 1/8 over a temperature range of 2.6 K. By comparing the results with the
Eb=
T phase diagram it is concluded that the ferroelectric III phase in thiourea is caused by the lock-in mechanism of the incommensurate lattice modulation period at 8
c0.
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Yasuo Morimoto
1982 Volume 51 Issue 4 Pages
1049-1053
Published: April 15, 1982
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Various types of I–V curves in two-terminal circuit are obtained by changing bias
V, and feedback resistance,
RF. Six states appear in the I–V curves. ON, OFF 1 and OFF 2-states are static. Decaying oscillation appears in I and III-states and constant amplitude oscillation occurs in II-state. On transition of circuit state, current noise increase and decay time elongation of the decaying oscillation are observed, which are similar to critical fluctuation and slowing down observed on phase transition of equilibrium systems. Thus the circuit can be said to undergo some kind of phase transition. Phase diagram is described in coordinate system of
V and
RF. There are two interesting points, one the presence of transition regions such as metastable and unstable states and the other the presence of singular points such as triple point and critical point, which resembles van der Waals type liquid-gas transition.
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Toshihico Arimitsu
1982 Volume 51 Issue 4 Pages
1054-1061
Published: April 15, 1982
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We prove microscopically that, in the long time limit, the interaction between classical Brownian particles (harmonic interaction) does not affect the relaxation terms, which are obtained by projecting out the linear dissipative reservoir systems, in
the limit of the Kramers’ equation. Without this limit, we show that the interaction does affect the relaxation terms even in the classical system.
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Yutaka Inaba
1982 Volume 51 Issue 4 Pages
1062-1069
Published: April 15, 1982
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A quantum-mechanical scattering theory is developed for the scattering by a potential of which strength is randomly fluctuating between two values with a switching rate γ⁄2. Within this model the
T matrix averaged over the fluctuation is derived exactly, from which the averaged scattering cross section (ACS) is obtained by using the optical theorem. Explicit calculations of the ACS are carried out for three cases; (i) within the Born approximation, (ii) for a separable potential, (iii) for a short-range potential in a lattice. It is found that the low-energy ACS is enhanced in comparison with the static case for
E⁄h\lesssimγ\lesssimh⁄(2
ma2) because of the large inelastic cross section, where
E is the energy of the incident particle with a mass
m and
a is the range of the potential.
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Toshihico Arimitsu, Fumiaki Shibata
1982 Volume 51 Issue 4 Pages
1070-1077
Published: April 15, 1982
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Theory of exchange dephasing in molecules is developed from a quantum statistical point of view. Use has been made of a time-convolution-less projection operator formalism presented by us earlier. Reservoir variables and fast exchanging mode are eliminated consistently giving a basic equation valid for any time scale and temperatures.
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Kenichi Nanbu
1982 Volume 51 Issue 4 Pages
1078-1079
Published: April 15, 1982
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An expression for the mean square displacement
E[|
X(
t)|
2] of a simulated molecule was obtained by using the covariance function for its velocity. It was shown that
E[|
X(
t)|
2]∼
t2 for a small time and
E[|
X(
t)|
2]∼
t for a large time.
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Toshihiko Ohta, Ryozo Aoki, Seiji Hayashi
1982 Volume 51 Issue 4 Pages
1080-1088
Published: April 15, 1982
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Indium films were overlayered on strontium titanate of various carrier concentrations by deposition in a ultrahigh vacuum, and their superconducting transition temperature
Tc was measured as a function of the film thickness and the carrier concentration
n of SrTiO
3−x. When
n was less than 10
20 cm
−3,
Tc of indium films did not differ so much from that on the reference quartz. However, when
n exceeded 2×10
20 cm
−3, a distinct decrease in
Tc was observed for films thinner than about 500 Å. This decrease in
Tc was attributed to the occurrence of the superconducting proximity effect between indium films and SrTiO
3−x, because the dependence of
Tc both on the film thickness and on the carrier concentration was reasonably explained in terms of McMillan’s model of the proximity effect and the estimated tunneling probability of electrons through the Schottky barrier.
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Kenji Takanaka
1982 Volume 51 Issue 4 Pages
1089-1094
Published: April 15, 1982
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Assuming that the superconducting phase difference in voltage biased Josephson tunnel junctions has only a single frequency component, the current-voltage (
I-
V) characteristics are studied and their stability is discussed. On the
n-th step which occurs at
eV=hω
n with the applied voltage
V and the
n-th resonance frequency ω
n(=
nω
1), it is found that the mode with the frequency ω
1 has a lower energy than that with the frequency ω
n. On all steps the radiation frequency from the junctions is therefore equal to ω
1 (the fundamental frequency) in accord with the experimental observations.
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Yôichi Fukagawa, Shun-ichi Kobayashi, Wataru Sasaki
1982 Volume 51 Issue 4 Pages
1095-1104
Published: April 15, 1982
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The NMR shift, line shape and spin-lattice relaxation time of superconducting small particles of Sn were measured at temperatures between 1.3 and 4.2 K and in magnetic fields between 5.6 and 30 kOe. The mean size ranged from 70 to 450 A in diameter. The critical field of the particles proved to be in agreement with the theory. In low fields, the fluctuation theory, which takes into account the effect of spin-orbit interaction, well reproduces the experimental results for large particles. The consideration of level quantization effect in addition to the fluctuation theory allows qualitative understanding of the results for smaller particles.
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Hidetoshi Fukuyama
1982 Volume 51 Issue 4 Pages
1105-1110
Published: April 15, 1982
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Interplays between strong spin-orbit scattering and Coulomb interactions are investigated for conductivity of two-dimensional disordered systems. Magnetoresistance is positive for both orientations of magnetic field relative to the system, but the characteristic fields are different.
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Antonio R. P. L. Albuquerque, Sadao Isotani
1982 Volume 51 Issue 4 Pages
1111-1118
Published: April 15, 1982
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EPR spectroscopy in X-Ray irradiated natural crystals of gypsum (CaSO
4 2H
2O) from Ceará, Brazil, showed the presence of four paramagnetic centers. The spectra of these centers were separated using temperature and power variations techniques. The
g and
A tensor parameters of two of these centers, identified as OH
· and O
2H
· were calculated.
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Kinshiro Hirakawa, Hideki Yoshizawa, Koji Ubukoshi
1982 Volume 51 Issue 4 Pages
1119-1122
Published: April 15, 1982
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Following the magnetic and X-ray crystallographic study on CsVCl
3 by Niel
et al., we performed susceptibility and neutron scattering measurements on the single crystal we prepared. A weak quasi-elastic scattering showing one-dimensional correlation has been found at temperatures lower than room temperature. At temperatures lower than
TN=13.3 K, a 3 D order with triangular spin arrangement has been found. Unexpectedly, the (1/3, 1/3, 1)
M magnetic Bragg scattering intensity starts decreasing at about 2 K down to 0.3 K.
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Tadamiki Hihara, Seiji Nishizawa, Kenichi Kojima, Takahiko Kamigaichi
1982 Volume 51 Issue 4 Pages
1123-1127
Published: April 15, 1982
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The
153Eu NMR in Eu
0.99Sr
0.01Se and Eu
0.99Sm
0.01Se have been observed as a function of temperature in the range between 1.7 and 4.2 K.
Each of the resonances in the magnetic phases of the NNS and NSNS types has one or two satellite lines, which are assigned to the nuclei having a Sr or Sm ion on the next nearest neighbor (n.n.n.) sites. The transferred hyperfine field per a n.n.n. Eu
2+ ion is obtained as −(4.1±0.4) kOe from the satellite NMR frequencies. The value agrees with that estimated by using the hyperfine splitting of the Eu
2+ ESR in SrSe, showing that the core polarization fields at the Eu
2+ nuclei in EuSe and SrSe are equal to each other.
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Hiroshi Takano, Ayao Okiji
1982 Volume 51 Issue 4 Pages
1128-1133
Published: April 15, 1982
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The explanation of phase diagrams about the mixed pyrite structure compounds NiS
2−xSe
x, Co
xNi
1−xS
2 and Ni
1−xCu
xS
2 in the nickel rich region is given with the use of the doubly degenerate Hubbard model. It is found that the overall nature of the phase diagram which includes the antiferromagnetic phase transition and the metal-nonmetal transition can be explained by introducing the intra-atomic exchange interaction.
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Kunitomo Hirai
1982 Volume 51 Issue 4 Pages
1134-1144
Published: April 15, 1982
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The method for calculating the electronic structure of transition metals which was developed before is applied to ferromagnetic, antiferromagnetic and helical spin density wave states. By use of the method, the magnitude of local moments, energy, etc. are calculated within the Hartree-Fock approximation. The relative stability of those states is investigated for a given valence, and phase diagrams of bcc and fcc transition metals are constructed. It is found that the most stable state changes continuously from an antiferromagnetic one to a ferromagnetic one via a helical spin density wave one when the valence changes from five to ten. The correspondence between the obtained phase diagrams and experimentally observed ones for 3
d metals is discussed.
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Norio Kawakami, Ayao Okiji
1982 Volume 51 Issue 4 Pages
1145-1152
Published: April 15, 1982
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Following the Wiegmann approach the exact expression of the ground state energy for the symmetric Anderson Hamiltonian was obtained. In this paper the calculation is done for the asymmetric Anderson Hamiltonian, of the ground state energy, of the average number of localized electrons and of the charge susceptibility.
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Masanori Matsunaga, Yoshikazu Ishikawa, Tetsuo Nakajima
1982 Volume 51 Issue 4 Pages
1153-1161
Published: April 15, 1982
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The magneto-volume effect of the weak itinerant ferromagnet MnSi has been studied by measuring both the thermal expansion over a wide range of temperature and the forced volume megnetostriction at different temperatures. The forced magnetostriction at 4.2 K as well as the magnetic thermal expansion at 10 kOe, Δω
m(
H,
T) can well be described by a formula Δω
m(
H,
T)=
KCΔ[
MST(
H,
T)
2] with
KC=1.5×10
−10 (mol/emu)
2 where Δ[
MST(
H,
T)
2] is the change of square of magnetization by polarization of the
d band. The spontaneous magnetostriction at 0 K, Δω
m(0, 0) is related to the spontaneous magnetization
M(0, 0) by Δω
m(0, 0)\doteqdot(2⁄5)
KC M(0, 0)
2 with the same
KC. Furthermore magneto-volume effect becomes positive above
Tc. All of these features agree satisfactorily with those predicted by Moriya and Usami based on spin fluctuation theory.
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Satoshi Hirosawa, Yoji Nakamura
1982 Volume 51 Issue 4 Pages
1162-1165
Published: April 15, 1982
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The spin orientation in the C-15 type pseudobinary Tb
1−xDy
xCo
2 system with strongly competing single-ion anisotropies of rare earth ions has been observed at 4.2 K by means of
59Co spin echo NMR. The spin is aligned ferrimagnetically along the [111] direction for 0≤
x≤0.3 and along the [001] direction for 0.8≤
x≤1. In the intermediate region with
x between 0.4 and 0.7, the external field dependence of the resonance frequency indicates that the
59Co hyperfine field is noncolinear in the total magnetization. A model which assumes spacially inhomogeneous spin orientations has been proposed.
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Makoto Okochi, Kohei Yagisawa
1982 Volume 51 Issue 4 Pages
1166-1175
Published: April 15, 1982
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Self-consistent APW band calculation has been performed for the intermetallic compound CoAl having the CsCl-type structure. The resulting density of states, partial densities of states, and Fermi surface are found to be favorably compared with the experimental values of electronic specific heat, Pauli susceptibility, X-ray emission spectroscopy, and Knight shift. Charge transfer has been related with the electrostatic Ewald potential felt by an electron in the interstitial region between atoms. This treatment has an advantage that the atomic volume is not necessary to be determined. The amount of charge transfer from aluminum to cobalt has been estimated to be 0.283. It has been found that the region delineated by the position of the maximum potential is electrically neutralized by the nuclear charge and the surrouning electrons, and has a close connection with the atomic size in the compound. The relation between the neutralized region and the atomic volume is discussed.
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Hisazumi Akai, Junjiro Kanamori
1982 Volume 51 Issue 4 Pages
1176-1184
Published: April 15, 1982
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A new method of calculation of the coherent potential approximation combined with the Korringa-Kohn-Rostoker method of the band structure calculation is proposed. The electronic structure of Fe–Al and Pd–Al alloys are calculated by this method. The concentration dependence of the electronic specific heat coefficient, the (high field) susceptibility and the nuclear spin-lattice relaxation time of the alloys is discussed in the light of the calculation.
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Eiji Anno, Ryosuke Hoshino
1982 Volume 51 Issue 4 Pages
1185-1192
Published: April 15, 1982
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The size dependence of the half width of the optical plasma resonance absorption of silver island films has been investigated at 293 K. Below a diameter of about 14 A the deviation from the classical prediction was observed. Considering the average energy level spacing and the level broadening due to scatterings, this deviation was attributed to the quantum size-effect. The level broadening estimated from electron-electron scattering in the optical region was of the order of the average energy level spacing of the particle of about 20 A in diameter. Furthermore, the half width was not changed from 293 to 85 K, which agrees with the prediction based on the temperature dependence of this scattering. Therefore, it was concluded that the conduction band is continuous down to diameters of about 20 A because of the level broadening due to electron-electron scattering.
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Hideo Asahina, Koichi Shindo, Akira Morita
1982 Volume 51 Issue 4 Pages
1193-1199
Published: April 15, 1982
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The energy band structure of black phosphorus is calculated by using self-consistent pseudopotential method. The resulting band structure has the direct minimum gap at the point
Z in the Brillouin zone in agreement with the result of the tight-binding approach. Effective electron and hole masses and the level shift of the band edge by pressure are calculated from the bands obtained. The pressure dependence of the energy gap is in good agreement with experiment, but the anisotropy of the effective masses contradicts that of the electrical conductivity measured for the single crystal. The nature of the optical absorption edge is discussed in terms of the calculated band structure.
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Yutaka Unuma, Yasuaki Masumoto, Shigeo Shionoya
1982 Volume 51 Issue 4 Pages
1200-1206
Published: April 15, 1982
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Time-dependence of the excitonic molecule luminescence in CuBr is measured at 4.2 K under the one-photon band-to-band excitation and the two-photon resonant excitation of excitonic molecules by using a picosecond tunable laser. The lifetimes of excitonic molecules and single excitons are determined to be 60 ps and 150 ps, respectively, by analyzing the results for the two cases of excitation. With these values of the lifetimes, the time-dependence of the luminescence under two types of excitation is explained self-consistently. The lifetime of molecules almost agrees with the radiative lifetime calculated by using existing theories. It is found that the probability of the formation of excitonic molecules per one collison of two single excitons is quite low, and that in the case of the resonant excitation the re-formation process of molecules is negligible.
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Nobuhiro Gemma, Akiko Natori, Hiroshi Kamimura
1982 Volume 51 Issue 4 Pages
1207-1215
Published: April 15, 1982
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Optical absorption spectra in low and intermediate concentrations of donor impurities are calculated by taking account of the excitonic interaction between a hole localized on a donor and a
D− ion. In calculating absorption spectra, the self-consistent Born approximation is adopted in order to treat both diagonal and off-diagonal disorder due to random distribution of donors, which appears in the excitonic and transfer terms of
D− states in the final state Hamiltonian, respectively. The interplay between excitonic and transfer effects in absorption spectra is investigated. It is shown that the broadening behavior of peaks in high energy region is due to transfer effect between donor excited states and delocalized exciton states while the broad tail in low energy region corresponds to the inhomogeneous broadening of the transitions to localized exciton states.
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Hiroshi Orihara, Takeo Ishidate, Akikatsu Sawada, Yoshihiro Ishibashi
1982 Volume 51 Issue 4 Pages
1216-1219
Published: April 15, 1982
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The phase transition of thiourea under high pressure has been investigated by means of second harmonic generation (SHG), pyroelectric and Raman scattering measurements. The high pressure phase VI turns out to be centrosymmetric as the results of the SHG and pyroelectric charge measurements. At high pressure some of new Raman-active modes were observed. On the basis of these experimental results it is guessed that the centrosymmetric high pressure phase VI of thiourea is induced by instability of a zone-boundary mode of the atmospheric pressure phase V.
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Yoshihiro Ishibashi
1982 Volume 51 Issue 4 Pages
1220-1222
Published: April 15, 1982
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The specific heat in an incommensurate phase of the K
2SeO
4-type crystals was calculated on the basis of the Landau-type thermodynamic potential functional, which was solved within the phase modulation-only approximation. It was found that the calculated specific heat decreases first with decreasing temperature and shows a small anomaly just above the incommensurate-commensurate transition temperature. The observed data of K
2SeO
4 and Rb
2ZnCl
4 seem to be well reproduced by adjusting parameters.
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Yoshichika Onuki, Rumiko Inada, Sei-ichi Tanuma
1982 Volume 51 Issue 4 Pages
1223-1227
Published: April 15, 1982
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The electrical resistivity of layered ZrSe
2 is found to be proportional to T
2 above 50 K, being similar to that of TiS
2. This behavior is discussed on the bases of the homopolar optical scattering and the electron-electron scattering.
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Noboru Miura, Yoshihiro Iwasa, Tohru Itakura, Giyuu Kido
1982 Volume 51 Issue 4 Pages
1228-1235
Published: April 15, 1982
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Shubnikov-de Haas oscillations were observed for
n-channel (100) Si MOS–FETs in pulsed high magnetic fields up to 37 T. Magnetic field dependence of the peak height of the transverse conductivity σ
xx associated with the
N=0 Landau level was investigated at various magnitudes of source-drain field at 1.9 K. In high magnetic field range, it was found that the height of the first of the four
N=0 peaks increased with increasing magnetic field when the source-drain field was relatively low. Similar increase of the peak height by magnetic field was also observed for the other three peaks. The number of immobile electrons in the lowest Landau level was also estimated, and it was found to increase as the magnetic field was increased. In addition, fine structures were observed between the gaps of the conductivity peaks.
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Junzo Tanaka, Masakatsu Umehara, Syuzo Tamura, Masayuki Tsukioka, Shaw ...
1982 Volume 51 Issue 4 Pages
1236-1242
Published: April 15, 1982
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Electric resistivities and thermoelectric powers of the system (La
0.8Ca
0.2)MnO
3−y were measured in several samples with
y less than 0.07, in which the amounts of the oxygen deficiencies
y were carefully controlled. The electrical conduction at
T>
Tc (
Tc denotes the magnetic transition temperature) is of an activation type, while at
T<
Tc, it changes from a degenerate type to an activation type with increasing
y. The thermoelectric power at
T>
Tc is proportional to 1/T in all samples and that at
T<
Tc shows a metalic behavior in the samples with
y=0.00 and 0.025. The activation energy estimated from the electric resistivity at
T>
Tc is about three times larger than that estimated from the thermoelectric power. These experimental results are discussed on the basis of the conventional semiconductor model.
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Akira Sugiyama
1982 Volume 51 Issue 4 Pages
1243-1247
Published: April 15, 1982
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Formation energy of an intrinsic stacking fault in copper is calculated by the use of two interionic potential functions given by Prakash and Lucasson. A modified Ewald method is used to calculate lattice sum of long-range interionic potentials expressed by
Vp sincos(2
kFr)⁄(2
kFr)
3. Numerical results show that 1) the two potential functions give 60.5 erg/cm
2 and 78.3 erg/cm
2 to the intrinsic stacking fault energy, and 2) the energy comes mainly from a long-range interaction but not from a short-range one. These potentials are used also for calculations of binding energies of fcc, bcc and hcp structures. Numerical results show that the fcc structure is stable and the binding energies of the bcc and the hcp structures are larger than that of the fcc by 0.06 eV/ion and 0.01 eV/ion, respectively.
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Toshiaki Shiraishi, Shoji Masunaga
1982 Volume 51 Issue 4 Pages
1248-1254
Published: April 15, 1982
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The adiabatic potential energy surfaces (APES’s) of Tl
+-type impurities in alkali halides,
3T1u(
Γ4−) and
3A1u(
Γ1−) have been calculated taking account of the spin-orbit interaction and both the linear and quadratic Jahn-Teller effect with the α
1g and ε
g vibrational modes. It has been found that the
3T1u APES’s have one kind of minima or the two kinds of minima, depending on whether we assume the linear or both the linear and quadratic Jahn-Teller interactions. A trap level
3A1u lies just below both the minima. The line shapes of the
A-emission and
A-absorption bands in KBr: Tl
+ are calculated by using the Franck-Condon and Condon approximations. It has been found that the theoretical line shape of the
A-emission band has the asymmetric doublet structure and reproduces the experimental emission bands
AT and
AX. This shows that the large energy differnce between the
AX and
AT bands is caused by the quadratic Jahn-Teller terms involving
Q1(α
1g).
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Shin-ichi Hirako, Ryumyo Onaka
1982 Volume 51 Issue 4 Pages
1255-1263
Published: April 15, 1982
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The UV and VUV spectra of Li-halide crystals doped with divalent transition metal ions are studied. The observed bands are assigned to the charge-transfer (C.T.) transitions from the halogen
p orbitals to the metal 3
d orbitals in the transition metal hexahalide complexes. The observed structures of C.T. bands are attributed to the level splitting of metal 3
d orbitals of the C.T. states by the crystal-field and intra-ionic electron-electron interactions, and the structures of the valence states consisting of halogen
p orbitals.
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Mitsuyoshi Matsushita
1982 Volume 51 Issue 4 Pages
1264-1273
Published: April 15, 1982
Released on J-STAGE: June 01, 2007
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Dechannelling of 1.5 MeV He
+ ions in planar channels of Al-6.8 at.% Zn and Al-8.2 at.%Ag alloy single crystals containing spherical G.P. zones was studied. Dechannelling cross sections of G.P. zones were obtained experimentaly from the normalized yields using single scattering model of dechannelling, and also calculated from the semi-analytical method based on the modified continuum model, taking account of both the lattice distortion around the zone and the sudden change of the planar potential at the zone. Lattice distortion around the G.P. zone was determined by comparison of the experimental and calculated dechannelling cross sections.
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Junichi Yoshida, Kiyosi O-Ohata
1982 Volume 51 Issue 4 Pages
1274-1281
Published: April 15, 1982
Released on J-STAGE: May 29, 2007
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Ab initio calculation with the configuration interaction method is used to obtain the potential curves and the diabatic coupling matrix elements for the OH
3+ system. The configuration interaction method reproduce the experimental values of the excitation energies in a good approximation. The radial coupling matrix elements related to the charge transfer reaction have large values at the avoided crossing points and also in the regions of the smaller nuclear distances. The rotational coupling matrix elements have nearly constant values at larger nuclear distances but change abruptly their values at the avoided crossing points.
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Norio Ohtomo, Kiyoshi Arakawa
1982 Volume 51 Issue 4 Pages
1282-1289
Published: April 15, 1982
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A statistical thermodynamic calculation of liquid Na–K alloys using a generalized van der Waals theory is performed. The theory combining the Lebowitz equation for a hard-sphere mixture with an energy term showing the
V−1⁄3-dependence (
V: volume) proves to be essentially successful to explain various thermodynamic properties (volume, enthalpy, entropy, concentration fluctuations, etc.) of the liquid alloys. The physical parameters (energy parameters, packing fraction, etc.) used in the calculation are determined by solving the equation of state directly. Structure factors calculated are found to reproduce well observed data. Some critical discussions about other theories are made.
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Keiichi Kamada, Chiharu Okada, Takashi Ikehata, Hiroshi Ishizuka, Syoi ...
1982 Volume 51 Issue 4 Pages
1290-1297
Published: April 15, 1982
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The interaction of an intense (
n∼10
11 cm
−3), pulsed (200 ns), proton beam (∼80 keV and ∼380 A) with a transverse magnetic field
B⊥ produced by a pair of mirror coils has been studied experimentally. The beam is space-charge-neutralized and can travel across the magnetic field up to 3 kG by forming polarization electric field due to charge separation, which cancels out the deflection by the Lorentz force
ν×
B. It is observed that beam expansion along
B⊥ gives rise to the density reduction in the course of travelling. A model is proposed, which relates the outward force along
B⊥ to the density reduction and can explain the experimental results.
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Nobuo Yajima
1982 Volume 51 Issue 4 Pages
1298-1302
Published: April 15, 1982
Released on J-STAGE: June 01, 2007
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The effect of a perturbation on a solitary wave is studied through an extension of Hirota’s method. The same result as those obtained by the ordinary singular perturbation technique and by the perturbation theory of the inverse spectral transform can be more straightforwardly and more easily derived.
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Takao Yoshinaga, Tsunehiko Kakutani
1982 Volume 51 Issue 4 Pages
1303-1309
Published: April 15, 1982
Released on J-STAGE: May 29, 2007
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Using a nonlinear
LC ladder line which simulates an anharmonic lattice, the asymptotic behaviour of a long wave in the absence of solitons has been studied experimentally. In this experiment, we observe that an input negative rectangular pulse produces, instead of solitons, a long negative triangular wave followed by a train of highly oscillatory waves. Both the leading triangular wave and the oscillatory waves decrease their amplitudes during a course of propagation. The amplitude, shape and decay rate of the leading wave observed by the experiment are well compared with those obtained from the numerical analysis of the line. A quantitative comparison is also made with the results based on the Korteweg-de Vries (K-dV) asymptotic theory.
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Katsumi Takenouchi, Noriaki Gohda
1982 Volume 51 Issue 4 Pages
1310-1319
Published: April 15, 1982
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The transient flow of a slightly conducting gas in a pipe under an applied magnetic field with axial symmetry is considered. The solutions to the linearized equations for subsonic flow show that in the asymptotic limit as
t→∞, these solutions do not necessarily all tend to coinside with the corresponding solutions to the steady flow, and differ from those by constants which are determined depending on the strength of the magnetic field and the initial values of the flow quantities. The time for the flow to achieve the steady state is also evaluated.
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Kinzo Hida
1982 Volume 51 Issue 4 Pages
1320-1323
Published: April 15, 1982
Released on J-STAGE: June 01, 2007
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The point of no reflection is newly defined as the point on the shock polar, where a spine and one of the characteristics are parallel. The number of such points is 0, 1, 3 or 2, depending on the Mach number in an upstream uniform flow. Physical meaning of this point is exemplified by taking a flow pattern past a wedge-like body in a supersonic flow.
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Hiroshi Hayashi
1982 Volume 51 Issue 4 Pages
1324
Published: April 15, 1982
Released on J-STAGE: June 01, 2007
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Yoshitoshi Muraoka, Toru Fujiwara, Masayuki Shiga, Yoji Nakamura
1982 Volume 51 Issue 4 Pages
1325
Published: April 15, 1982
Released on J-STAGE: May 29, 2007
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