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A. K. Sharma, R. Kaur, H. R. Verma, P. N. Trehan
1980 年 48 巻 5 号 p.
1407-1414
発行日: 1980/05/15
公開日: 2007/05/29
ジャーナル
認証あり
The properties of the gamma transitions emitted in the decay of
152Eu and
154Eu have been studied. The energies and relative intensities of 87 and 82 gamma rays from the decays of
152Eu and
154Eu respectively, have been precisely measured. The precision in the present energies and intensities is in general much better than the earlier reported results. These measurements also confirm the existence of several controversial weak gamma transitions involved in these decays.
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H. R. Verma, S. S. Sooch, R. Kaur, A. K. Sharma, Nirmal Singh, P. N. T ...
1980 年 48 巻 5 号 p.
1415-1422
発行日: 1980/05/15
公開日: 2007/05/29
ジャーナル
認証あり
The energies and relative intensities of 51 gamma transitions following the β
− decay of
125gSn have been precisely measured. Six gamma transitions of energy 487.2, 890.5, 903.5, 912.0, 1291.3 and 2038.3 keV have been observed for the first time. Out of these, the 890.5, 903.5 and 912.0 keV γ-transitions have been placed in the decay scheme of
125gSn. The present study reveals that the earlier reported gamma transitions of 398.1, 1137.5 and 2227.0 keV can not be attributed to
125gSn decay.
The directional correlations in
125Sb have been done on 13 cascades with improved time resolution. Based on these measurements, the 2240.4 and 2288.0 keV levels have been assigned the characters 9/2
+ and 11/2
+ respectively. The multipole admixtures in the 12 gamma transitions have been evaluated.
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Kazuhiro Takahashi, Motoyuki Tanaka
1980 年 48 巻 5 号 p.
1423-1428
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
Phase transitions of the spin-one Ising system with bilinear and biquadratic interactions in the existence of the anisotropy energy are investigated using a constant-coupling theory developed in the preceding paper. Characteristic features of possible phase transitions found in this system are made clear by illustrating a three-dimensional phase diagram. It is then shown that there exist several types of single phase transition or successive phase transitions according to the energy parameters. The variations of the order parameters with temperature below and above these phase transitions are also investigated.
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Ikuo Ono
1980 年 48 巻 5 号 p.
1429-1438
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
An ordered phase with the generalized spin orientation of the Ising model consisting of ferro- (A) and antiferromagnetic (B) bond-mixture is investigated in detail on a triangular cactus tree in the case of
JA=−
JB=
J(>0). The long and short range order-parameter are able to be defined clearly, and thus these quantities, energy and spin-pair correlations are estimated at various temperatures and bond-concentrations. At the transition temperature a jump in the specific heat and a cusp in the uniform susceptibility are found. Some of calculated results are considerably good agreement with those obtained from Monte Carlo simulations on a triangular lattice.
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Yoshio Ishizawa, Hiroshi Nozaki, Takaho Tanaka, Tetsuo Nakajima
1980 年 48 巻 5 号 p.
1439-1442
発行日: 1980/05/15
公開日: 2007/05/29
ジャーナル
認証あり
Angular variations of de Haas-van Alphen frequencies of the order of 10
4 gauss in LaB
6 have been studied in the low magnetic fields by the torque method. These frequencies are interpreted as interconnecting necks between nearly spherical ellipsoids which are centered at the points X in the simple cubic Brillouin zone. The magnetic breakdown field is estimated to be about 150 kOe from the Fermi surface parameter. These results are consistent with already reported de Haas-van Alphen data.
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Kiiti Siratori, Eiji Kita
1980 年 48 巻 5 号 p.
1443-1448
発行日: 1980/05/15
公開日: 2007/05/29
ジャーナル
認証あり
Magnetoelectric effect was observed in ZnCr
2Se
4 below 20 K, in the state of screw spin structure. Magnetic field dependence of the effect at 4.2 K was qualitatively interpreted by the appearance of Dzyaloshinski interaction, when the field was applied along [001] or
k0, the wave vector representing the screw structure. When the field direction is changed, however, the effect was rather difficult to be accounted for.
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João Baptista Domiciano, Walter Sano, Klemensas Rimgauadas Jura ...
1980 年 48 巻 5 号 p.
1449-1452
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
EPR of Ni
2+ diluted in single crystal of Zn(BF
4)
26H
2O was recorded between 98 and 298 K. The thermal variations of the spin Hamiltonian parameters
g⁄⁄,
g⊥ and
D, and the linewidth of the spectra showed anomalous behavior when compared with previous work in the isomorphous Ni(BF
4)
26H
2O. The anomalies are attributed to a phase transition of second order with
Tc≅181 K.
D varies linearly with temperature and the linewidth as
ΔH=
a+
bT2 similar to verified previously in the Ni compound. The phase transition occurs with a change in the coefficients of these laws. From the linewidth, a spin-lattice relaxation time
T1 is determined as 10
−9 to 10
−10 s.
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Hitoshi Yamazaki, Edmundo Soares, Horácio Panepucci, Yukio Mori ...
1980 年 48 巻 5 号 p.
1453-1459
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
Subthreshold parallel pumping of magnons in the quasi-one-dimensional ferromagnet, CsNiF
3, is investigated at 70, 90 and 120 GHz at temperatures between 1.3 and 4.2 K. The absorption line shape which is anisotropic in the easy-plane is found to be proportional to the magnon density of states which is calculated by using the following parameters: intrachain ferromagnetic exchange field
HE=300 kOe, interchain antiferromagnetic exchange field
HE′=−1200 Oe, magnetization
M=240 emu/cm
3 and anisotropy field
HA=58 kOe. One of the two peaks which are the peculiar features of the magnon density of states in quasi-one-dimensional ferromagnets is revealed by this experiment.
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Yoshio Kitaoka, Hiroshi Yasuoka
1980 年 48 巻 5 号 p.
1460-1469
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
The properties of the spin density fluctuations in the itinerant antiferromagnetic compounds V
3Se
4 and V
5Se
8 have been investigated in both the paramagnetic and the antiferromagnetic states by using the pulsed NMR technique. The temperature dependences of the uniform susceptibilities χ
u(
T), the staggered moments
MQ(
T) and the nuclear spin-lattice relaxation rates 1/
T1 of
51V for both V
3Se
4 and V
5Se
8 are well explained within a framework of the self-consistent renormalization (SCR) theory of spin fluctuations for weak itinerant antiferromagnets. The Curie-Weiss like behavior of χ
u(
T) and the temperature independent contribution to the 1/
T1 observed in V
5Se
8 are concluded to be due to the effect of the spin fluctuation components around
q=0 which, in addition to those around
q=
Q (
Q being antiferromagnetic wave vector), play an important role in determining the magnetic properties.
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Hidetaro Abe
1980 年 48 巻 5 号 p.
1470-1475
発行日: 1980/05/15
公開日: 2007/05/29
ジャーナル
認証あり
The Co
2+ ions at two different sites in Zn(HCOO)
2·2H
2O have been studied in their ESR at about 9.37 GHz and between 1.6 and 50 K. The temperature dependence of the spin-lattice relaxation time deduced from the line width depends on the site and can be well explained by the Orbach type process, if the energy difference
Δ, between the ground and the first excited Kramers doublet, is 89 and 160 cm
−1, respectively. A theoretical calculation based on their anisotropic
g-tensors gives 140 and 215 cm
−1, if λ=−120 cm
−1 is assumed.
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Hozumi Kagawa, Soshin Chikazumi
1980 年 48 巻 5 号 p.
1476-1481
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
Magnetic and thermal properties of Fe–Ni Invar single crystals were studied through the measurement of magnetic anisotropy energy and thermal expansion along the principal crystallographic axes. It was found that the magnetocrystalline anisotropy constant,
K1, at 4.2 K is reduced from 5.4×10
4 erg/cc at 36.8 at.% Ni–Fe to less than 1×10
4 erg/cc at ∼30.8 at.% Ni–Fe. This behaviour is quite similar to that of magnetic moment, lattice constants and so on.
The anomalous uniaxial magnetic anisotropy energy constant,
Ku, and the anisotropic thermal expansion coefficient, α
a, (
Ku≈0.25×10
4 erg/cc and α
a≈0.8×10
−6·K
−1 at 300 K) were observed in some Invar alloys. This anomalous behaviour is considered to be due to anisotropic distribution of Fe–Fe atom pairs.
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Takeo Jo
1980 年 48 巻 5 号 p.
1482-1489
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
The electronic structure in the ground state and the response to the magnetic field of Ni–Mn alloys are investigated with use of the Hartree-Fock-Coherent Potential Approximation (HF–CPA) approach. The calculation which distinguishes Mn atoms having antiparallel moments to the bulk magnetization from those with parallel moments shows the occurrence of the second order phase transition at the critical Mn concentration from the ferromagnetic state to
the spin glass state in the absence of the magnetic field. The calculated spin susceptibility and bulk magnetization as functions of the magnetic field and the Mn concentration well reproduce the recent experimental results.
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Tôru Moriya, Hideo Hasegawa
1980 年 48 巻 5 号 p.
1490-1503
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
A unified description is given for magnetism of narrow band electron systems on the basis of a functional integral formalism within the static approximation. A method is developed to calculate the free energy functional from a given band structure and its closed form expression is given for arbitrary amplitudes of the spin and charge density fluctuations, correponding to arbitrary strength of the electron-electron interaction. This expression is shown to lead to essentially correct results in both the weak and strong coupling limits. The metal-insulator (Mott) transition and related magnetic properties for the case of half-filled band and the magnetism of metals in the case of non-integral occupation number per atom are discussed with a numerical example for a tight-binding band in a simple cubic lattice.
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Hiroshi Katayama-Yoshida, Kiyoyuki Terakura, Junjiro Kanamori
1980 年 48 巻 5 号 p.
1504-1512
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
The electronic structure of substitutional impurities, Cu, Zn, Ga, Ge, As, Se, Br and Kr in ferromagnetic nickel is calculated with a muffin-tin potential model for the purpose of discussing the hyperfine field
Hhf and the spin-lattice relaxation time
T1. The calculated
Hhf on the basis of the direct Fermi contact interaction with valence electrons is in good agreement with experimental data. A detailed discussion which is substantiated by the calculation is given on the underlying mechanism of the systematic variation of
Hhf in a period of the Periodic Table which is observed in other periods as well as the one mentioned above. (
T1T)
−1 arising from the direct Fermi contact interaction is concluded to show a similar systematic variation, although the orbital relaxation mechanism makes an important contribution in the case of Cu to make it exceptional.
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Yoshihiro Yamada, Hideo Ohmae
1980 年 48 巻 5 号 p.
1513-1518
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
The NMR technique was employed to study the magnetic behavior of Co in psudo-binary Laves phase compounds, Y(Fe
1−xCo
x)
2 and Zr(Fe
1−xCo
x)
2 over the whole concentration range of
x. The change of spin echo spectra in Fe rich side with increasing Co shows that the Co moment decreases slightly in
x≤0.3 and then decreases rapidly in Y(Fe, Co)
2, while decreases rapidly in Zr(Fe, Co)
2 from the start. In critical concentration for destruction of ferromagnetism the coexistence of magnetic and nonmagnetic Co was shown by
59Co NMR observations both in zero and in external field. The Co moment is probably induced by magnetic Fe in its near neighbors.
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Yoshihiro Shiozaki, Shuzo Kawarazaki
1980 年 48 巻 5 号 p.
1519-1531
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
The electrical resistivity of dilute
AuCr alloys (2∼320 at.ppm) was measured in a temperature range between 0.5 K and 300 K and the results were analyzed in terms of the generalized phase shift approach (GPS) developed by Soultie. A set of physical quantities representing the Kondo effect has been obtained.
The Kondo temperature and the magnetic moment of Cr impurity deduced from the resistivity data using the GPS model were compared with those determined by the nuclear orientation and the susceptibility experiments and a satisfactory agreement has been obtained.
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Kohei Higuchi, Hiroyoshi Suematsu, Sei-ichi Tanuma
1980 年 48 巻 5 号 p.
1532-1540
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
The de Haas-van Alphen (dHvA) effect in C
8K, C
36K and C
48K has been studied. Five dHvA periods in C
48K and two periods in C
36K are observed, each of which has the angular dependence being close to cos θ, where θ stands for the angle between the
c-axis and the magnetic field. These periods are interpreted in terms of the rigid band model based on the three-dimensional graphite band added by the band folding due to the
c-axis superlattice of the intercalate layers. In C
8K, one period is observed and interpreted by the cylindrical Fermi surface which is given in the band calculation by Inoshita
et al. The charge transfer rate from potassium to the graphite band is estimated as 0.21 for C
48K and 0.17 for C
36K from these dHvA periods.
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Hiroyoshi Suematsu, Kohei Higuchi, Sei-ichi Tanuma
1980 年 48 巻 5 号 p.
1541-1549
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
Resistivity (ρ), Hall coefficient (
RH) and transverse magnetoresistance (tMR) of C
8K(1st) and C
12NK(
N-th stage,
N=2, 3 and 4) at temperatures of 1.2 to 300 K have been investigated in connection with the study of the Fermi surfaces (Part I). Resistivities in the
N≥2 stage compounds show some anomalies which are associated with the order-disorder phase transitions. In C
8K, ρ has a temperature dependence of
a+
bT+
cT2. The temperature dependence of
RH indicates the one-electron conduction for the
N≥2 compounds and the two-carriers one for C
8K. The tMR of each compound is represented by a linear function of magnetic field at about 4 to 15 T. The angular dependence of tMR indicates the cylindrical Fermi surface in a whole. The charge transfer rate from potassium to the graphite band is evaluated as 0.1 to 0.4 electron per atom for the 1st to 4th stage compounds.
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Tyuzi Ohyama, Eizo Otsuka
1980 年 48 巻 5 号 p.
1550-1558
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
For the exciton system coexisting with a strain-confined large electron-hole drop in germanium, a time constant as long as 1500 μs is observed by far-infrared. Combining this with the decay data of the drop, a quasi-steady state between the drop and its clinging exciton system is confirmed. A relevant excitonic atmosphere is defined around the drop with an effective thickness dependent on the drop radius and temperature. The critical temperature of the liquid
Tc is estimated to be 6 K.
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Tyuzi Ohyama, Isao Honbori, Eizo Otsuka
1980 年 48 巻 5 号 p.
1559-1565
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
The Alfven wave dimensional reonance for a strain-confined large electron-hole drop in germanium is observed in microwave absorption experiments at various temperatures. From the linewidth measurement, the average carrier relaxation rate in the drop is calculated. It has temperature dependence of the form 1⁄τ
av=
aT2+
b with
a=(1.2±0.1)×10
9 K
−2s
−1 and
b=(1.4±0.1)×10
10 s
−1. It is strongly suggested that the temperature dependence of the relaxation is mainly due to carrier-carrier scattering. In addition, the isothermal compressibility for the large drop is estimated to be
KT=(2.3±0.2)×10
−2 cm
2dyne
−1.
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Tetsuro Saso, Tadao Kasuya
1980 年 48 巻 5 号 p.
1566-1575
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
Resistivities and Hall coefficients of heavily doped semiconductors in the metallic concentration range, especially of Sb-doped Ge and P-doped Si, are investigated by the degenerate electron gas model with impurity scattering. The maxima of resistivity and Hall coefficient are explained by strong temperature variation of the screening length, which is due to the smallness of the Fermi temperature
TF in the present systems (
TF∼100 K). The shapes of the screened impurity potentials and the scattering of electrons by them are investigated in detail by the nonlinear Hartree approximation, the Kohn-Sham density functional formalism and the random phase approximation with valley multiplicity. Including nonlinearity of screening and many-body effect, we obtain the values of resistivity which agree very well with experiments for the higher concentration samples of the metallic range.
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Yukio Noda, Robert Youngblood, Gen Shirane, Yasusada Yamada
1980 年 48 巻 5 号 p.
1576-1587
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
The phase transition of KD
3(SeO
3)
2 has been investigated by means of neutron scattering. The transverse acoustic phonon mode corresponding to the C
44 stiffness constant (C
44 TA mode) was measured along (0, 0, ξ) from ξ=0.025 to the zone boundary ξ=0.5. The spectral density of the C
44 TA mode is anomalous for 0.05<ξ<0.2. Above this region, the phonon is unrenormalized and is well defined. Below the anomalous region, the TA mode shows soft phonon behavior which agrees well with the ultrasonic and the Brillouin scattering experiments. The neutron result is interpreted to mean that the TA mode shows crossover behavior through the regime of relaxational hydrogen motion. Another possible explanation of the anomalous behavior of the TA mode is coupling to a soft optical mode. A search for such a mode was performed, with negative results.
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Terutaro Nakamura, Vladimir Fridkin, Rukman Magomadov, Masaaki Takashi ...
1980 年 48 巻 5 号 p.
1588-1592
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
The first observation of the anomalous photovoltaic effect and the photorefractive effect in a Rb
2ZnBr
4 crystal is reported. The Glass constant and the photovoltaic current in this crystal has been found to be of the same order of magnitude as those in LiNbO
3 : Fe, although the spontaneous polarization of Rb
2ZnBr
4 is very low, that is, three orders of magnitude lower than that in oxygen octahedra ferroelectrics. Neither photovoltaic effect nor photorefractive effect is observed in the incommensurate phase. The photorefractive effect in this crystal is understood to be caused by the photovoltaic effect.
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Yoshihiro Shiozaki, Shuzo Kawarazaki
1980 年 48 巻 5 号 p.
1593-1600
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
Deviations from the Matthiessen’s rule (DMR) have been extracted from experimental data of the electrical resistivity of dilute
AuCr alloys (2∼320 at.ppm) measured in a temperature range between 0.5 K and 300 K.
Magnetic scattering by Cr impurities has shown no special effect on the DMR compared to nonmagnetic impurity scattering.
The initial rise of the DMR in the alloys has a temperature dependence with an exponent of about 4, while that of Cu-based alloys in the same concentration range is about 3. This fact is attributed to the low Debye temperature of Au matrix.
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Yoshitake Ueda, Takao Kino
1980 年 48 巻 5 号 p.
1601-1606
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
The longitudinal magnetoresistance of high-purity aluminium single crystals has been measured by point-contact four-probe method at 4.2 K in the magnetic fields up to 4 T. Squeezing effect of a current is recognized in all specimens, and anisotropy of the squeezing effect, which is induced by magnetic breakdown, is observed in specimens having specific orientations.
The saturation values of the longitudinal magnetoresistance at 4.2 K along the principal axes [001], [111] and [011] are obtained as 0.36, 0.8 and 1.1, respectively.
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Kunio Tsukioka, Taizo Masumi
1980 年 48 巻 5 号 p.
1607-1617
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
A cyclotron resonance experiment of polarons in AgBr has been performed at 34 GHz over the temperature range 2∼23 K with pulsed laser excitation up to the excitation density G∼10
28 photons/cm
3sec. A remarkable broadening of resonance line at high density excitation is interpreted in terms of the polaron-exciton interaction from the energy dependence and the magnitude of the scattering probability. A numerical analysis of the kinetics of the polaron-exciton system supports this interpretation. Time resolved measurements were performed in nanosecond region. At high levels of excitation, a nonresonant absorption due to unknown origin was observed at the delay time
Td=15 nsec.
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Kazuo Soda, Noriaki Itoh
1980 年 48 巻 5 号 p.
1618-1624
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
Measurements have been made of the creation of the
F centers by the optical excitation of the self-trapped excitons with a light pulse from a tunable dye laser. It is found that the ratio of the
F-center concentration created by the light pulse to the triplet exciton concentration at the incidence of the light pulse depends on the integrated photon flux
Φ as
a{1−exp (−
bΦ)}, where
a and
b are constants. Kinetic models are developed for treating the non-radiative processes of the highly excited self-trapped exciton, and the efficiency of the
F-center creation from the highly excited triplet exciton was determined using the experimentally obtained parameters
a and
b. It is found that the efficiency is almost constant between 1.77 and 2.08 eV above the lowest triplet exciton and becomes higher above 2.58 eV. The dependence of the efficiency on energy is discussed in terms of existing models of the defect formation.
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Jimpei Harada, Satoshi Yao, Ayahiko Ichimiya
1980 年 48 巻 5 号 p.
1625-1630
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
Fine gold particles prepared by gas evaporation technique were characterized by X-ray powder diffraction method. Several anomalies which are similar to those found in the cold worked metal fillings were found in the Debye-Scherrer pattern. Obvious differences in lattice parameter and the thermal expansion coefficient were not detected between the fine gold particles with the mean size of 100 A and bulk crystal. The mean square atomic displacement estimated from the Debye-Waller factor, however, shows sometimes values twice as large as that of the bulk crystal, depending on specimen preparation. It is shown that a considerable contribution from static lattice distortions is included in the mean square atomic displacement.
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Ken-ichi Ohshima, Atsuo Hayashi, Jimpei Harada
1980 年 48 巻 5 号 p.
1631-1635
発行日: 1980/05/15
公開日: 2007/05/29
ジャーナル
認証あり
From an analysis of the X-ray Debye-Scherrer lines from fine gold particles with the mean size of 100 A, the mean square atomic displacement, 〈
u2〉, was determined at several temperatures in a range from 112 to 298 K. The temperature dependence of 〈
u2〉 was analysed on the basis of the Einstein approximation for the thermal vibrations of atoms and a characteristic temperature θ
E=143±3 K was obtained. This is 15% less than the Debye temperature θ
M=168 K for the bulk crystal. It was found that the observed 〈
u2〉 includes the temperature independent component, impling the existence of some kind of static lattice distortions. The contribution from such lattice distortions depends on the preparation condition of fine gold particles.
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Kensuke Ikeda, Jumpei Okada, Masahiro Matsuoka
1980 年 48 巻 5 号 p.
1636-1645
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
The time evolution of the cascade emission from an assembly of the three-level atoms excited by two-photon process is investigated under a linear approximation. The propagation effect and the stochastic nature of the quantum noise are fully taken into account. It is found that the time evolution of the emitted radiation shows different behaviors in the three time stages: In the earliest stage a negative feedback mechanism due to the two-photon coherence is important, and the emitted radiation exhibits a characteristic growing behavior peculiar to the cascade system; in the intermediate one this mechanism is destroyed by the dephasing, and a superradiant growth begins; and finally in the latest one this growth is suppressed by the dephasing of the active polarization, and a stationary radiation appears.
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Kensuke Ikeda, Jumpei Okada, Masahiro Matsuoka
1980 年 48 巻 5 号 p.
1646-1654
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
The characteristics of the cooperative cascade emission is studied by taking into account of the nonlinearity due to depopulation. It is shown that the emitted radiation exhibits considerably different behaviors in three regimes of the atomic number density. In the lowest density regime the radiation is essentially a quasi-stationary amplified spontaneous emission (ASE), in the intermediate one it becomes superradiant, and in the highest one it shows a new cooperative behavior peculiar to the cascade system. By using the present theory the experimental results recently observed in Li vapour is explained. It is also shown that the present theory describes the two-level cooperative emission as a specific limiting case.
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Satoshi Hashimoto, Yasuko Ohiwa
1980 年 48 巻 5 号 p.
1655-1660
発行日: 1980/05/15
公開日: 2007/05/29
ジャーナル
認証あり
The C band of Pb
++ centers in LiI, NaI, KI and RbI crystals does not show a triplet structure at 77 K. The weak B band of KI : Pb and RbI : Pb lies at low energy side of the C band, whereas that of NaI : Pb and LiI : Pb does not appear separately from the C band. Suppression of the C bands and increasing of the splittings between the C and D′ bands are caused by substituting the host crystals in the order of RbI, KI, NaI and LiI, which is qualitatively interpreted in connection with the configuration interaction between an excited state of Pb
++ and an electron transfer state. In addition, temperature sensitive band appears between C and D′ bands of NaI : Pb and LiI : Pb.
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Toshiaki Ohsaka
1980 年 48 巻 5 号 p.
1661-1668
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
The frequency and linewidth of the four Raman active modes in anatase have been investigated over the temperature range 20 to 1100 K. The temperature (
T) dependence of the frequency of the 639 cm
−1 mode showed typical behavior in normal ionic crystals, whereas the other modes at 399, 197 and 144 cm
−1 did anomalous behavior. These
T dependent results were combined with pressure dependent results, thermal expansion and compressibility data to evaluate the pure-volume and pure-temperature contributions to the
T dependence of each frequency. The results indicate that the anomalous
T dependence of the 399 cm
−1 mode reflects the near cancellation of the cubic and quartic contributions to the frequency shift, and that of the modes at 197 and 144 cm
−1 arises from strong quartic contributions. The
T dependence of the linewidth is well explained qualitatively in terms of simple anharmonic effects involving three phonon processes.
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Kunihiko Morimoto
1980 年 48 巻 5 号 p.
1669-1677
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
The effect of the tunneling motion of NH
4-ion on the nitrogen spin-lattice relaxation time
T1N has been calculated on the basis of the semi-first-order perturbation theory of Haupt. It is shown that the nitrogen spin, which is coupled with the proton spins by the dipole-dipole interaction, relaxes through the tunneling system of protons and then the measurement of
T1N is useful to investigate the quantum NH
4-ions.
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Tetsuo Koizumi, Nobuo Kobayashi, Yazaburo Kaneko
1980 年 48 巻 5 号 p.
1678-1682
発行日: 1980/05/15
公開日: 2007/05/29
ジャーナル
認証あり
Mobilities of Ne
+ and Ar
+ ions in He gas were studied at 82K. An injected-ion drift tube mass spectrometer, the drift tube of which can be cooled with liquid nitrogen was developed for this purpose. The mobility curves obtained have a bump at intermediate
E⁄
N, and the zero-field reduced mobilities have approached to the polarization limits. The He peculiarities which have been known for long time are explained clearly by the temperature effects found in this work.
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Kazuhiro Sakimoto
1980 年 48 巻 5 号 p.
1683-1690
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
A good convergency of the semiclassical PRS method, developed recently by K. Takayanagi (J. Phys. Soc. Jpn.
45 (1978) 976, referred to as I), has been confirmed. The straight-line trajectory treatment has proved to be a good approximation for the low-energy ion-polar molecule collision where the long-range dipole interaction is dominant. A scaling low derived in I is found useful for predicting rotational excitation cross sections for a large number of collision pairs.
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Yo Mizuta
1980 年 48 巻 5 号 p.
1691-1701
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
Consideration is given on the shape of the allowed and satellite lines in the spectra of radiation emitted by a He-like radiator in a magnetized turbulent plasma. The satellite is considered to be induced by a high-frequency, coherent and spatially inhomogeneous electric field oscillating in the direction parallel or perpendicular to the static magnetic field. The frequency of the electric field is supposed to be near-resonant to the interval between upper two levels. The effects of degeneracy and the magnetic field are treated exactly. Numerical calculations are presented for a set of levels
nu1D,
nu1P and
n11S (
nu=3, 4, 5, 6,
n1=2). For the linearly polarized electric field perpendicular to the magnetic field, some zero points and gaps appear in the satellite which are not expected in the case of the circularly polarized electric field.
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Masato Mushiage, Kozaburo Tamura, Hideoki Hoshino, Hirohisa Endo
1980 年 48 巻 5 号 p.
1702-1706
発行日: 1980/05/15
公開日: 2007/05/29
ジャーナル
認証あり
The pressure variations of the two-phase region and liquidus curve in the Se-rich region of the liquid Tl–Se mixtures have been determined. It was found that the two-phase region disappears at about 7 kbar, and then the S-shape liquidus curve appears. The Tl-rich end of the monotectic line moves towards Se-rich concentration with pressure, while the Se-rich end seems hardly to change.
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Yoshio Kita, Kei-ichi Hirano
1980 年 48 巻 5 号 p.
1707-1714
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
MHD instabilities which destroy a stable reversed field pinch (RFP) plasma are investigated in a small tight aspect ratio torus, STP-1. Special attention is paid on programing of setting up the RFP configuration. It starts with screw pinch and then external fields is reversed while the plasma current is kept increasing in order to maintain equilibrium relation with respect to minor radius of the plasma. Consequently plasma-wall interaction during RFP setting up phase is minimized and increased trapped toroidal flux by factor two is achieved compared with usual programing mode. In this way a stable RFP plasma is created with density of 3.5×10
15/cm
3, temperature of 20 eV and discharge current of 58 kA. After 13 μsec stable operation time, the plasma is rapidly deformed and moves from its equilibrium position by a violent MHD
m=1 instability, of which structures are observed by
Br magnetic probes. A theoretical calculation of one dimensional stability analysis based on ideal MHD model is applied to our experimental results. It is found that the instability may be
m=1 resistive tearing mode under the influence of viscosity.
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Hiroatsu Maki, Keishiro Niu
1980 年 48 巻 5 号 p.
1715-1721
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
On the basis of linear theory, the increase in the kinetic energy is analyzed for electrons which are accelerated by the resonance field in the laser-irradiated target. The duration of a constant resonance-field energy and the dynamical balance between the ponderomotive force and the pressure gradient near the resonance point lead us a relation among the temperature of fast electrons, the laser-power flux and the background-electron temperature. It is shown that the generation of fast electrons is suppressed when a suitable condition is kept between the background-electron temperature and the laser-power flux.
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Shinji Tokuda, Tetsuo Kamimura, Hiroshi Ito
1980 年 48 巻 5 号 p.
1722-1730
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
The collisionless drift wave instability driven by an electron temperature inhomogeneity (electron temperature gradient instability) and the enhanced transport processes associated with it are studied using a two-and-a-half dimensional particle simulation code. The simulation results show that quasilinear diffusion in phase space is an important mechanism for the saturation of this instability. The instability yields particle fluxes toward the hot plasma regions. The magnetic shear stabilizes the instability. However the heat conductivity of the electron temperature perpendicular to the magnetic field,
Te⊥, is not reduced by the magnetic shear but remains high, whereas the heat conductivity of the parallel temperature,
Te⁄⁄, is effectively reduced.
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Kazumi Ohasa
1980 年 48 巻 5 号 p.
1731-1737
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
Numerical studies on linear growth rate of resistive tearing mode in current carrying stellarator fields are presented for various plasma current profiles (flattened, parabolic and peaked) and helical fields (
l=2 and
l=3). The linear growth rate is calculated by solving linearized magnetohydrodynamic equation as initial and boundary value problem for various cases of plasma parameters, field configurations and boundary conditions.
An
l=2 helical field stabilizes the tearing mode but
l=3 helical field has a tendency to destabilize it. Effects of the boundary condition on the growth rate are appreciable when a singular surface is near plasma boundary and plasma resistivity is not small.
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Tadayoshi Murata
1980 年 48 巻 5 号 p.
1738-1745
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
The steady motion of a flexible solid particle in a quienscent unbounded viscous fluid is investigated theoretically. It is assumed that the particle is a homogeneous, isotropic elastic body obeying Hooke’s law and that the undeformed particle is spherical in shape. It is further assumed that the motion of fluid obeys the Stokes equation. It is shown that for small values of the parameter α=η
U0⁄
GR0, where η is the shear viscosity of fluid,
G the shear modulus of the particle and
U0 the terminal settling velocity of a rigid particle whose radius is
R0, the particle deforms into a prolate spheroid and the deviation from a sphere is in proportion to α
2. The effect of the deformation on the terminal settling velocity of the particle is also included in the analysis.
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Kazuo Matsuuchi
1980 年 48 巻 5 号 p.
1746-1754
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
Nonlinear interactions between two waves travelling in opposite directions are investigated. When a nonlinear Klein-Gordon equation is adopted as a model equation, it is shown that such a wave system is governed by a simple set of equations for their complex amplitudes. Steady progressive waves governed by this set are investigated for various cases classified according to the signs of the coefficients. It is then found that one wave travelling in one direction appears from a certain point and the other travelling in the opposite direction has a constant amplitude from that point. This phenomenon may be regarded as a sort of reflection in spite of no rigid boundary.
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Akira Nakamura, Ryogo Hirota
1980 年 48 巻 5 号 p.
1755-1762
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
It is shown that the Bäcklund transformation of the modified KdV equation generates a new nonlinear evolution equation of the type (
Remark: Graphics omitted.), (with μ, μ′ representing arbitrary parameters) which we call “second modified KdV” equation. Exact multi-soliton solution of the equation is obtained.
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Osamu Sano, Hidenori Hashimoto
1980 年 48 巻 5 号 p.
1763-1768
発行日: 1980/05/15
公開日: 2007/06/01
ジャーナル
認証あり
A theoretical study is made of the purely three-dimensional steady Stokes flow induced by a point force in a region bounded by two plane walls intersecting at an angle 2α. If 2α is less than 146.3°, an infinite sequence of deformed eddy rings surrounding the direction of the stokeslet appears near or far from the corner for the special case when the point force is applied perpendicularly to the bisector of the wedge. The intensities and sizes of adjacent eddies decrease in geometric progression at the same common ratios as those in the two-dimensional case described by Moffatt. The streamlines within the plane which is perpendicular to the intersection and which contains the stokeslet are not the shame as the two-dimensional ones, and the lines through the center of each eddy rings form a family of eccentric circles on the bisector.
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Kuon Inoue, Toshiyuki Sameshima
1980 年 48 巻 5 号 p.
1769
発行日: 1980/05/15
公開日: 2007/05/29
ジャーナル
認証あり
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Fumitake Itoh, Toshihisa Honda, Koichi Niihara, Toshio Hirai, Kenji Su ...
1980 年 48 巻 5 号 p.
1770
発行日: 1980/05/15
公開日: 2007/05/29
ジャーナル
認証あり
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Hiroshi Mollymoto, Eiji Fujiwara, Mitsuhiro Motokawa, Muneyuki Date
1980 年 48 巻 5 号 p.
1771-1772
発行日: 1980/05/15
公開日: 2007/05/29
ジャーナル
認証あり
Magnetization measurements of two low-dimensional antiferromagnets copper benzoate Cu(C
6H
5COO)
2·3H
2O and copper tetra-amine sulfate Cu(NH
3)
4SO
4·H
2O (CTS) were done at liquid helium temperatures under a pulsed high field up to 400 kOe. The modified critical field
Hc′ of the antiferromagnetic-paramagnetic transition is obtained to be 266±15 and 100±5 kOe for copper benzoate and CTS, respectively. The spin contraction effect in the antiferromagnetic spin short range order state is clearly found below
Hc′.
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Akikatsu Sawada, Jun Sugiyama, Mitsuo Wada, Yoshihiro Ishibashi
1980 年 48 巻 5 号 p.
1773-1774
発行日: 1980/05/15
公開日: 2007/05/29
ジャーナル
認証あり
Successive phase transition in {N(CH
3)
4}
2CuCl
4 has been studied by polarization microscopic observation and by the measurement of dielectric constant. A new phase transition is found to take place at intermediate temperature (about 8°C on cooling, about 18°C on heating) between the two phase transition points at 24°C and −9.4°C previously reported. Evidence is presented that the phase transition is the one from an incommensurate phase to a ferroelastic (commensurate) phase.
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