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Takakazu Shintomi, Chiri Yamaguchi, Masayoshi Masuda
1971 Volume 31 Issue 5 Pages
1297-1303
Published: November 05, 1971
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Energy and angular distributions of the photoprotons from the
40Ca(γ,
p)
39K reaction have been measured using the bremsstrahlung beams with the end point energies of 25.5, 23.0, 20.5 and 18.0 MeV from a 31 MeV betatron. The dipole strengths are concentrated in the giant resonance region and are divided into seven peaks at 18.1, 18.7, 19.2, 19.9, 20.4, 20.9 and 21.5 MeV, rather strongly at 18.7, 19.2, 19.9 and 20.4 MeV.
No significant peaks are observed above 22.5 MeV, which indicate that the absorptions in this energy region mainly lead the residual nucleus to the excited states and hardly to the ground. The asymmetric angular distributions around 90° observed in both sides of the giant resonance region suggest the existance of the absorption of M1 or E2. Collective correlation must be added to the shell model in order to explain the experimental results.
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Kazumasa Miyano
1971 Volume 31 Issue 5 Pages
1304-1305
Published: November 05, 1971
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The slow neutron capture cross section for
171Er was obtained to be (2.8±0.3)×10
2 barns by irradiating natural Er with the high flux pile. The (n, γ) reaction cross section for
171Tm, far from the stable isotope
169Tm, was determined to be (1.6
−1.0+0.3)×10
2 barns in this irradiation.
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Michisuke Kobayashi, Kazuo Yamada
1971 Volume 31 Issue 5 Pages
1306-1312
Published: November 05, 1971
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The electron (hole)-phonon coupling and the dispersion relation of sound wave in semimetals under strong magnetic field are discussed. The discussion is based on an appropriate model from which the direct influence of conduction carriers on the sound propagation and on the carrier-phonon coupling can be separately taken out. Renormalization procedure through the polarization effects by the Coulomb interaction is carried out in the random phase approximation, which is shown to be applicable to the conduction carriers in bismuth. An anomalous behavior in phonon frequency takes place in a different form from the one in a previous work by Blank and Kaner. This anomaly in the quantum limit is explicitly calculated, taking the spin splitting into account. It is seen that depending on the relative magnitude of the effective spin mass to the orbital mass, the anomalous behavior may occur in longer region or in the shorter one of phonon wave-length.
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Masahiro Inoue, Makoto Okazaki
1971 Volume 31 Issue 5 Pages
1313-1322
Published: November 05, 1971
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Energy band structure of TlCl is calculated by means of the Heine-Abarenkov model potential method. In the process of evaluation of model potential parameters for Tl
+ ion, different suitable extrapolation energies are taken for calculation of the valence and conduction bands respectively. Nonlocal and relativistic effects of the potential are included in the calculation.
It is found that both the top of the valence band and the bottom of the conduction band are located at the point X which mainly consist of Tl-6s and Tl-6p characters, respectively. Result shows a substantial degree of mixing of Tl-6s and Cl-3p states in the overall structure of the valence bands. Interpretation of the optical absorption spectrum is also made.
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Junzo Chihara, Ken Sasaki, Yukio Obata
1971 Volume 31 Issue 5 Pages
1323-1328
Published: November 05, 1971
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It is shown that three kinetic methods [i) initial-value approach, ii) dielectric approach and iii) method of fluctuations in distribution function] for calculating the space-time correlation function using the Vlasov-Boltzmann equation are equivalent to one another, provided that the effective potential in the kinetic equation is proportional to the direct correlation function. This same condition brings the exact zeroth and second moments of the dynamic structure factor
S(
Q, ω) obtained by the kinetic method. These moment sum rules are independent of the collision term.
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Yoshiaki Muda
1971 Volume 31 Issue 5 Pages
1329-1336
Published: November 05, 1971
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First-principles OPW energy-band calculations have been made for metallic sodium in two different types of exchange approximations. First a
k-dependent core-conduction exchange potential has been derived from the Hartree-Fock equations with the use of the available core and conduction electron wave functions, and combined with the conduction-conduction exchange potential of ρ
1⁄3 type. Then the Knight shift parameter
PF=−〈|ψ
kF(0)|
2〉
av is found to be 0.362 a.u. (80% of the experimental value). The Fermi surface is also in reasonable agreement with experiment. Second the statistical exchange of Slater with a scale factor α (the
Xα method) has been examined, varying α from 1 to 0.9, 0.81, 0.74, and to 2/3. The best result has been obtained with α=0.81. At this α, the Fermi surface is in good agreement with experiment, but the value of
PF is like those of the earlier calculations based on the Prokofjew potential.
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Ryuzo Abe, Ken’ichi Okamoto
1971 Volume 31 Issue 5 Pages
1337-1343
Published: November 05, 1971
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An improvement of the Feynman action is discussed by introducing two additional parameters to Feynman’s original polaron theory. Both upper bounds of the ground state energy and corrections to the polaron mass are obtained for some values of the coupling constant. However, corrections are so small that Feynman’s trial action is proved to be a very good description of the polaron state.
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Hideji Yamada, Masao Shimizu
1971 Volume 31 Issue 5 Pages
1344-1349
Published: November 05, 1971
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The relaxation times of spin waves in ferromagnetic dilute alloys of transition metals are calculated in the Wolff-Clogston model for dilute alloys, by using the random phase approximation and by taking into account exchange interactions among electrons in the host metal. It is found that there are two mechanisms of the damping of spin waves by an impurity
i. e., ordinary scatterings of spin waves and decompositions of spin waves into individual particles of an electron with down spin and a hole with up spin. It is shown that the relaxation time of a spin wave in the former process has the same dependence on the wave vector of the spin wave as that obtained in the Heisenberg model and the latter process of the damping of a spin wave is important in unsaturated ferromagnetic dilute alloys.
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Norberto Majlis, Santiago Harriague
1971 Volume 31 Issue 5 Pages
1350-1354
Published: November 05, 1971
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Magnetic excitations localized on the (001) surface of a cubic Heisenberg ferromagnet are considered theoretically by extending previous calculations by several authors, where only a simple cubic spin lattice was considered, to b. c. c. and f. c. c. spin lattices.
The method can be easily generalized to any crystal symmetry, or any orientation of the axis of magnetization, assumed normal to the surface. This extension of the theory makes it possible to undertake in the future a comparison of theoretical calculations of the surface magnon despersionrelation, with, for instance, results of experiments with inelastic low energy electron diffraction on surfaces of,
e. g., some ferromagnetic rare-earth salts.
The relationship has been shown between the surface spectrum and the analytic continuation to the complex
k3 plane of the bulk magnon dispersion relation, where a very close analogy can be found with the theory of surface electronic states in semiconductors.
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Kazuo Kanematsu
1971 Volume 31 Issue 5 Pages
1355-1360
Published: November 05, 1971
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Laves phase compounds Zr(Fe, Co)
2 have MgCu
2 structure and Zr(Fe, Mn)
2 change the structure from MgCu
2 type to MgZn
2 type with composition change. Both compounds change from ferromagnetism to paramagnetism with decreasing Fe content and the magnetic moment of Fe, Mn, Co decrease from 1.62, 0.62, 0.62 μ
B to zero. This decrease is caused by a change of the local symmetry of the nearest neighbors in Zr(Fe, Mn)
2 and by a change of the configuration in Zr(Fe, Co)
2. An effect of configuration for the magnetic moments in Zr(Fe, Co)
2 is evaluated and compared with the hyperfine fields of Fe reported by Swartzendruber and Bennet.
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Takeshi Hiraoka, Morio Suzuki
1971 Volume 31 Issue 5 Pages
1361-1365
Published: November 05, 1971
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Measurements of orientational and forced magnetoresistances have been done on Gd single crystals in a range from 77 K to 400 K. According to a phenomenological analysis, the four anisotropy constants of the orientational magnetoresistance were determined. The temperature dependence of the orientational magnetoresistance showed generally two minima and a maximum, While the constants showed single minimum. This appears to be attributable partly to the variation of the easy direction with temperature. The temperature dependence of the forced magnetoresistance also was anisotropic. This seems to be related to the variation of the electrical resistance with temperature.
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Yasunori Tanji
1971 Volume 31 Issue 5 Pages
1366-1373
Published: November 05, 1971
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The thermal expansion coefficient α of Fe–Ni (
fcc) alloys was measured in the range from 800°C to room temperature. Below the Curie temperature
Tc, the α−
T curve exhibits an anomaly corresponding to the spontaneous volume magnetostriction ω
s. The
‘paramagnetic’ thermal expansion coefficient α
p below
Tc was determined by the extrapolation of the α−
T curve above
Tc and the value of ω
s was estimated from the difference between α
p and α below
Tc. The relation between ω
s and the change of
Tc with pressure was discussed. The α
p vs. composition curve at a fixed temperature shows a minimum around the invar alloys. This minimum corresponds to the anomaly in the elastic moduli vs. composition curves. It is thus pointed out that the lattice energy must be considered in addition to the magnetic energy in discussing the origin of the invar properties.
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Kunito Okamoto, Takashi Hashimoto, Kazuhiro Hara, Eiji Tatsumoto
1971 Volume 31 Issue 5 Pages
1374-1379
Published: November 05, 1971
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Detailed electron microscopic investigations confirmed that the shape anisotropies of the columnar grains grown in iron films evaporated at oblique incidence, which are parallel and perpendicular to the columnar grain axis, are principally responsible for both of the anisotropy fields
Hk(1) and
Hk(2) analyzed from torque measurements, respectively. Fiber textures found by X-ray diffraction were of the types of {111} and {100} perpendicular to the columnar grain axis, having minor contribution to
Hk(1) and
Hk(2), but appearing to have some connection with their rapid increase with increasing angle of oblique incidence.
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Yasutaro Uesaka, Ikuji Tsujikawa, Kiyoshi Aoyagi, Kuniro Tsushima, Sat ...
1971 Volume 31 Issue 5 Pages
1380-1390
Published: November 05, 1971
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The absorption spectrum of DyCrO
3 in the red region was studied with and without a magnetic field. From the Zeeman spectrum of a Dy
3+ ion, the anisotropy axis of a Dy
3+ ion was determined to be directed along the axis deviated by ±30° from the
b-axis in the
ab-plane. The magnitudes of the excitation transfer between the Cr
3+ ions with parallel spin (0.25 cm
−1) and with antiparallel spin (0 cm
−1) were obtained by analyzing the exciton lines associated with the Cr
3+ t2g3 4A2g→
t2g3 2Eg transition. Remarkable shifts of the exciton lines were observed in magnetic fields parallel to the
b-axis. Magnetic-field dependence of these shifts indicated that they were induced by some Dy
3+-Cr
3+ interaction. An electric-dipole line creating a Cr
3+ exciton and a Dy
3+ spin flip was also observed, from which a negative dispersion of the Cr
3+ exciton was found to be at least −16 cm
−1.
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Takeshi Komaru, Tadamiki Hihara, Yoshitaka Koi
1971 Volume 31 Issue 5 Pages
1391-1398
Published: November 05, 1971
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The Eu
153 NMR in EuSe has been observed as a function of temperature and applied magnetic field. NMR results in zero applied field support the magnetic structure proposed by Fischer
et al.; EuSe has a structure of the NNSS-type in the antiferromagnetic region (from 4.6 K down to about 2.5 K) and a structure in which there coexist the NNS-and NSNS-types in the ferrimagnetic region (below about 2.5 K). As the applied field is increased, the zerofield magnetic structure changes into an intermediate one and finally into the ferromagnetic one (NNN). The coexistence of a canted spin structure and a ferrimagnetic one is proposed for the intermediate phase.
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Teruya Sinjo, Harold Forstat
1971 Volume 31 Issue 5 Pages
1399-1402
Published: November 05, 1971
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The temperature dependence of internal magnetic fields in Fe
3(PO
4)
28H
2O was obserbed by the Mössbauer effect. It was made clear that although the temperature dependences of the two sublattices are greatly different, both internal fields disappear at the same temperature, 9.0 K. Measurements were also made at 4.2 K in the presence of an external field up to 50 kOe, whose direction was perpendicular to the crystal ac plane where the two spin easy directions are included. The ferromagnetic spin flipping occurred only at the sublattice of Fe I.
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Hideoki Kadomatsu, Eiji Tatsumoto, Hironobu Fujii, Tetsuhiko Okamoto
1971 Volume 31 Issue 5 Pages
1403-1407
Published: November 05, 1971
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Variation of the anisotropy constant
K1 with hydrostatic pressure was determined on 1.08 wt. % Si–Fe and Ni from torque measurements under pressures up to about 5 kbar at 77, 195, 238 and 291 K. The pressure coefficient at absolute zero, (1⁄
K1(0))(
ΔK1(0)⁄
Δp), was estimated by extrapolation as −2.1×10
−5 bar
−1 for the Si–Fe and −1.4×10
−5 bar
−1 for Ni. The temperature dependence of the anisotropy constant at constant volume,
K1V, deduced with (1⁄
K1)(
ΔK1⁄
Δp) at all temperature appears to obey the ninth power of the magnetization for the Si–Fe.
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Kazunobu Hayakawa, Kazumichi Namikawa, Shizuo Miyake
1971 Volume 31 Issue 5 Pages
1408-1417
Published: November 05, 1971
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The nature of exchange reflexions in low-energy electron diffraction from antiferromagnetic nickel oxide was studied in particular reference to its dependence on the diffraction condition of electrons, which was, in the present study, changed primarily by rotating the crystal at a fixed electron energy. It was pointed out that the exchange reflexions are subject to the three-dimensional diffraction conditions appropriate to the reciprocal lattice points which correspond to the magnetic structure, and also that the intensities of these weak reflexions may be favourably enhanced by the dynamical diffraction effect under the condition which involves the simultaneous presence of a strong regular reflexion.
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N. Malathi, S. P. Puri
1971 Volume 31 Issue 5 Pages
1418-1423
Published: November 05, 1971
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Mössbauer studies of Fe
3+ ions on Si-gel, Al
2O
3 and a natural zeolite mineral natrolite, treated with Fe(NO
3)
3 and FeCl
3 solutions and subsequently heated in steps upto 950°C, have been carried out to study the adsorption and change of chemical species caused by thermal treatment. It is inferred that iron ions exist as superparamagnetic particles of α-FeOOH on all the surfaces studied upto 200°C. Further heating to 400°C, transforms it partly into fine particles of α-Fe
2O
3, the conversion however, becoming complete by 600°C. At 800–950°C, Fe
3+ enters the Al
2O
3 lattice substitutionally, while in the case of Si-gel, α-Fe
2O
3 particles register an increase in crystallite size only. In the case of natrolite, there results particles of α-Fe
2O
3 with size greater than 150 Å, when heated to 800–950°C.
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Kenzo Igaki, Nobumitsu Ohashi, Masao Mikami
1971 Volume 31 Issue 5 Pages
1424-1430
Published: November 05, 1971
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Composition analysis and vapor pressure measurement on the chromium sulfides prepared under the controlled pressures and temperatures indicated that the equilibrium sulfur pressure for the CrS
x increases monotonically with the increasing sulfur content in both ranges of 1.200<
x<1.390 and 1.420<
x<1.480 and is kept constant in the range of 1.390<
x<1.420 corresponding to the coexistence of two crystalline phases. The existence of two crystalline phases with 1.420<
x<1.463 and 1.463<
x<1.480 was estimated from the abrupt change in the heat of vaporization of sulfur in the CrS
x at
x≈1.463. The hexagonal unit cell dimension of the superstructure for
x=1.200 is expressed in terms of \sqrt3
a and 2
c. Fox
x=1.333, monoclinic deformation is observed. The magnetic susceptibility of single crystals with the various controlled compositions was measured.
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Shigeo Yamaguchi, Takaaki Hanyu
1971 Volume 31 Issue 5 Pages
1431-1441
Published: November 05, 1971
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The dielectric constant of potassium is determined from 2.07 eV to 6.2 eV by using only
s-polarized light. The ε
1-spectrum is expressed by 1.23-(λ/2920)
2 in λ<3600A and 1.14-(λ/2990)
2 in λ>3600A. The ε
1- and ε
2-spectra are compared with the other published data, and discussed with the sum rule and the dispersion relation. The loss function is separated from the absorption spectrum for
p-polarized light, and is compared with the calculated loss function from the dielectric constant. The two loss functions seem to be different in the half width.
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Shun-ich Kobayashi, Toshihiro Takahashi, Wataru Sasaki
1971 Volume 31 Issue 5 Pages
1442-1445
Published: November 05, 1971
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Metallic fine particles of Al with diameters of less than 100 Å are studied by NMR and magnetic susceptibility measurements at low temperatures to verify discrete energy level effect of conduction electrons. Different behaviors of particles with odd and even electron numbers are observed in NMR line shapes. Odd particles tend to have high paramagnetic susceptibility while even particles tend to zero paramagnetism. No appreciable enhancement of superconducting transition temperature is observed in fine particles. Some measurements of Cu particles are also carried out to be compared with Al particles.
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Tetsuya Kawakubo
1971 Volume 31 Issue 5 Pages
1446-1449
Published: November 05, 1971
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The fluorescence spectra of pure 1-methylnaphthalene and 1, 6-dimethylnaphthalene at 77 K and the fluorescence spectra from sublimation flakes of 2-methylnaphthalene and 2, 6-dimethylnaphthalene at room temperature have been measured. The spectrum of 1-dimethylnaphthalene, which is cooled down rapidly to 77 K, is broad and shows no vibrational structure. The emission of 1, 6-dimethylnaphthalene at 77 K has a broad band in the lower energy region and is attributed to an emission from the excimer. The intensities of emission from sublimation flakes of 2-dimethylnaphthalene and 2, 6-dimethylnaphthalene change on the exposure to exciting light. The post-irradiation intensity of the former decreases to one third as great as that before irradiation, but that of the latter increases up to three times. Also the mechanism of these phenomena is discussed.
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Mitsuhiko Hayashi
1971 Volume 31 Issue 5 Pages
1450-1454
Published: November 05, 1971
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The switching rate of TGS under mechanical stresses has been measured at room temperature by the pulsing method. Hydrostatic pressure (\lesssim2 k bar) decreases while two-dimensional pressure (\lesssim50 bar) perpendicular to the ferroelectric
b axis increases the switching rate. The exponential law is followed at every constant pressure of both types, and the activation field α increases linearly at the rate: (∂α⁄∂
p)⁄α=(8.5±1.3)×10
−11 cgs with hydrostatic pressure and decreases linearly at the rate: (∂α⁄∂
p)⁄α=−(3.9±0.3)×10
−9 cgs with two-dimensional pressure, where
p represents the magnitude of both types of pressure. These results agree with the prediction of Miller-Weinreich theory.
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Atsushi Suzuki, Shigeo Shionoya
1971 Volume 31 Issue 5 Pages
1455-1461
Published: November 05, 1971
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Using a ZnS:Cu, Al crystal grown from the melt, precise measurements were made at liquid helium temperature on the relationship between the decay rate of the green-copper luminescence and those of two kinds of photoinduced absorptions, one due to holes created at copper acceptors, and the other due to electrons trapped at aluminum donors. It was found that the decay rates of the two kinds of absorptions are equal to each other, and are about one half of that of the luminescence. This fact clearly incicates that the green-copper luminescence is caused by the recombination of electrons trapped at aluminum donors with holes trapped at copper acceptors according to the bimolecular kinetics, and provides the direct experimental evidence for the conclusion of the donor-acceptor pair emission mechanism for this luminescence presented in the previous investigations.
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Atsushi Suzuki, Shigeo Shionoya
1971 Volume 31 Issue 5 Pages
1462-1468
Published: November 05, 1971
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The polarization characteristics of the green-copper luminescence were investigated at liquid helium temperature using a melt-grown ZnS:Cu, Al crystal with cubic structure involving stacking faults. In accord with the results of the previous study at liquid nitrogen temperature, the luminescence is polarized preferentially perpendicular to the [111]
c axis. The origin of this polarization is attributed to the crystal field with trigonal nature of the host lattice, and the polarization characteristics are interpreted on the basis of the donor-acceptor pair emission mechanism. With increasing temperature from liquid helium temperature,
I⊥ decreases while
I|| increases keeping
I=
I⊥+
I|| constant,
I⊥ and
I|| being the intensities of luminescence polarized perpendicular and parallel to the [111]
c axis. These facts are accounted for, if one takes the thermal excitation of holes associated with copper acceptors into account.
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Kôki Takita, Takaaki Hagiwara, Shoji Tanaka
1971 Volume 31 Issue 5 Pages
1469-1478
Published: November 05, 1971
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Galvanomagnetic effects of
p-type tellurium were investigated in the wide temperature range from 77 K to 0.05 K under magnetic fields up to 18 kOe. The samples were not intentionally doped and their carrier concentrations were ranging from 1.9 to 6.6×10
14 cm
−3. Anomalous behaviors in the temperature dependences of the conductivity and the Hall coefficient and in the magnetic field dependences of the Hall coefficient were observed below liquid helium temperatures. Furthermore these behaviors were different from those in slightly Sb-doped crystals. These could be explained by introducing a new kind of two-carrier model, in which the impurity band-like states exist below the top of the valence band. A role of lattice defects in forming the impurity band-like states was discussed in relation to the electronic structure of tellurium.
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Isamu Todo, Itaru Tatsuzaki
1971 Volume 31 Issue 5 Pages
1479-1482
Published: November 05, 1971
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The anomalous ultrasonic attenuations α
0 of longitudinal waves propagating along the
c axis in Ca
2Sr(C
2H
5COO)
6 have been studied near Curie temperature
Tc in the paraelectric phase. The sound waves couple with electric polarizations by an electrostrictive interaction in the present study. The attenuation does not obey a simple power law such as (
T−
Tc)
n. The results are discussed in comparison with those in NaCO
2.
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Koji Ando, Soitiro Tosima
1971 Volume 31 Issue 5 Pages
1483-1492
Published: November 05, 1971
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Propagation and amplification of density waves in
p-InSb were investigated at 77 K. The electron-hole plasma was produced by double injection and the plasma density wave perturbed in the frequency range from 2-25 MHz at the injecting contact. The density perturbation propagates through the sample as a density wave with an ambipolar density velocity. The amplitude of the wave was observed to be spacially amplified when the electric field and the injection level were sufficiently high. The amplification constant was studied as a function of the frequency and the injection level. The experimental results are compared with the theories for the instability and it is concluded that the most probable mechanisms for the observed amplification are the effect of hot electrons on the ambipolar diffusion constant and the nonuniformity of the plasma density distribution.
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Tadashi Akahane
1971 Volume 31 Issue 5 Pages
1493-1504
Published: November 05, 1971
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The nonlocal magneto-conductivity tensor of an ellipsoidal Fermi surface in Voigt configuration is calculated. The components of it can be written as linear combinations of the components of the slightly modified nonlocal magneto-conductivity tensor of a spherical Fermi surface. Using these results, cyclotron absorption spectra of Bi are numerically calculated and compared with the experimental results obtained by Smith
et al. It is found that almost all the structures which cannot be understandable by the local theory can be attributed to the harmonics of the cyclotron resonances of holes and electrons induced by the spatial dispersion.
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Shohei Wakita
1971 Volume 31 Issue 5 Pages
1505-1512
Published: November 05, 1971
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The luminescence of KBr crystals containing KI of various concentrations between 0 and 100 mole % under X-ray irradiation and UV illumination has been investigated at liquid helium temperature. The two characteristic emission bands are observed at about 3.50 eV and 4.30 eV. The former band at 3.50 eV is shown to originate from the recombination of an electron with the self-trapped hole of the complex
Vk-center, IBr
− and π-polarized with a degree of polarization
P=−0.15±0.03. From the excitation spectra for this band by UV illumination, a possibility of energy transfer between excited Br
− ions and I
− ions is discussed. The latter band at 4.30 eV is due to a cluster of I
− ions.
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Kazuko Kubo
1971 Volume 31 Issue 5 Pages
1513-1520
Published: November 05, 1971
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Dislocation loop families beneath the cleavage face have been studied three-dimensionally by means of the electrolytic coloration. Emerge planes are {110} and (001). Dislocations at shallow levels are strongly influenced by image force,
i. e. freed from the face or changed their shape. The nucleation sources of dislocation are found at structural inhomogeneities where stress concentration occurs during the cleavage and electrolysis. Simple loop families are relatively isolated from each other, while complicated ones are observed to be close together with the multiform neighborhood. The mechanisms of nucleation and complication are discussed for each dislocation loop family, from simple to complicated ones including newly found chevron patterns.
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Kêitsiro Aizu
1971 Volume 31 Issue 5 Pages
1521-1526
Published: November 05, 1971
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It is hypothesized that the transformation of NaNH
4 tartrate from the prototypic phase to the ferroelectric and ferroelastic phase is caused by instability of a pair of conjugate lattice vibration modes with the wave normal in the orthorhombic
b direction and with the wave length equal to 3
b. Then the strange dielectric anomaly of NaNH
4 tartrate which has been observed by Jona
et al. Takagi
et al. is deduced naturally. Also, peculiar elastic and piezoelectric anomalies to be observed are deduced.
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Hidenao Sugawara, Hirofumi Fujimoto
1971 Volume 31 Issue 5 Pages
1527-1531
Published: November 05, 1971
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Isochromats of copper were investigated at the wavelengths corresponding to characteristic Cu
Kα
1 and
Kα
2 lines, and also at wavelengths of the continuous radiations near the Cu
K absorption edge. Apparatus used consisted of an ultra-high-vacuum X-ray tube, a curved quartz crystal spectrometer and a GM counter.
Results are as follows; at the characteristic
Kα
1 and
Kα
2 wavelengths the observed isochromats show the same threshold voltage as well as similar structures with some difference in their intensity. For the continuous radiations, four curves observed at different wavelengths within 15 volts around the edge agree in structure. Hence, it is inferred that the presence of a
K-hole does not lead to an essential difference in the feature of isochromat. The differences observed in the intensity may be interpreted in terms of the electron population and the self-absorption of X rays within the target.
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Yukikazu Itikawa
1971 Volume 31 Issue 5 Pages
1532-1535
Published: November 05, 1971
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The rotational excitation of a polyatomic molecule by electron collision is considered as caused by the polarization interaction as well as by the electrostatic one. It is shown how to incorporate the polarization effect into the Born formula previously derived for the rotational cross sections of symmetric-top molecules. Numerical examples are given for the electron-NH
3, –H
2O, and –H
2CO collisions.
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Kunihiko Iwasa, Nobuhisa Imai
1971 Volume 31 Issue 5 Pages
1536-1538
Published: November 05, 1971
Released on J-STAGE: June 01, 2007
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In the two dimensional case, the Poisson-Boltzmann equation is transformed into a special expression which relates the force acting on the polymers to the difference between the mean concentration
c and the activity
a.
Making use of this expression, the additivity rules of activity and of osmosis are derived. It is also demonstrated that this expression has an interesting property respect to the system which contains monovalent and polyvalent ions of the same sign.
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Sadao Nakamura, Hiroshi Kubo, Kenji Mitani
1971 Volume 31 Issue 5 Pages
1539-1543
Published: November 05, 1971
Released on J-STAGE: June 01, 2007
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The damping of right (R)-hand circularly polarized microwave through a magneto cesium plasma are investigated experimentally. The R-wave damps sharply at electron cyclotron frequency ω
c, and is power absorption coefficient and refractive index are about 0.33/cm and 1.0 respectively under the conditions of (ω
p⁄ω)
2=9.8×10
−5 and
Te=3500 K, where ω
p⁄ω and
Te are the normalized electron density and the electron temperature. These results are in reasonable agreement with the electron cyclotron damping predicted by the hot plasma theory.
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Kenya Matsuura
1971 Volume 31 Issue 5 Pages
1544-1552
Published: November 05, 1971
Released on J-STAGE: June 01, 2007
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The well-known magnetohydrodynamic equilibrium equations are reduced to the equations of convenient forms for the purpose of an investigation for equilibria of axially asymmetric toroidal plasmas with diffuse boundaries by introducing two scalar functions corresponding to a stream function in an axially symmetric case. In the reductions, it is assumed that the toroidal effect is small; namely the quantities of the configurations are expanded in a ratio of the minor radius to the major radius in toroidal system. Mainly, configurations of bumpy type and helical type are considered. In the former case, the forms of the resultant solutions give us a picture of the bumpy type configuration which has helical character as the toroidal effect. The helical type configuration in the latter case has no longer completely helically symmetric structures because of its toroidal effect.
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Tetsu Miyamoto
1971 Volume 31 Issue 5 Pages
1553-1559
Published: November 05, 1971
Released on J-STAGE: June 01, 2007
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The implosion of a plasma in the theta pinch is studied by the modified snow plow equations, where finite thickness of the imploding plasma layer is taken into consideration. They are derived from the magnetohydrodynamic equations for the extreme case in which the conductivity of the initial plasma is infinite, and are solved under the approximation of thin layer. When the conductivity of the initial plasma is zero, they can be applied also if the shock front is infinitesimally thin. They reduce to the usual snow plow equation in the limit of zero thickness. It is shown that the layer position, predicted by the usual snow plow model, is between the average radius and the outer radius of the layer. The modified snow plow equations give the knowledges of the exchange of the supplied energy for the kinetic and internal energy, as well as motions of the imploding layer. In the limit of thin layer, the total energy is equally distributed among the kinetic and internal energies.
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S. S. Chawla
1971 Volume 31 Issue 5 Pages
1560-1566
Published: November 05, 1971
Released on J-STAGE: June 01, 2007
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The effect of a uniform normal magnetic field upon the free convection from a vertical wall is considered when an instantaneous heat flux is released from the wall. Solutions for small and large times are obtained, using Laplace transform technique. In the ultimate state, a steady streaming, confined within the Hartmann layer emerges. At all stages of the motion, the shearing stress at the wall is less than its corresponding value the non-magnetic case, provided the thermal diffusivity is less than the magnetic diffusivity.
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Hideyuki Niimi
1971 Volume 31 Issue 5 Pages
1567-1571
Published: November 05, 1971
Released on J-STAGE: June 01, 2007
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The motion of a stratified fluid between two parallel infinite disks rotating with slightly different angular velocities is investigated on the basis of a linearized equation. The influence of stratification on the rotating fluid is elucidated in the two cases that the temperatures of the disks are given and that the heat flow from the upper to the lower disk is given.
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Kyoji Yamamoto
1971 Volume 31 Issue 5 Pages
1572-1575
Published: November 05, 1971
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The problem of a porous and permeable sphere in a uniform flow at small Reynolds number is considered. It is assumed that the Stokes equation holds outside the sphere and generalized Darcy’s law holds inside the sphere. A simple closed solution which depends on permeability of the sphere is derived. A formula for the drag acting on the sphere is also obtained.
It is found that for small permeability the flow in the sphere is governed essentially by Darcy’s law except at a boundary layer near the surface of the sphere. A proper boundary condition at the surface for the Stokes equation and Darcy’s law is given when the latter is assumed to hold all over the sphere by neglecting the boundary layer.
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Akira Yoshizawa
1971 Volume 31 Issue 5 Pages
1576-1580
Published: November 05, 1971
Released on J-STAGE: June 01, 2007
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The laminar viscous flow past a finite flat plate set parallel to a uniform stream is studied by solving the Navier-Stokes equations numerically in the neighborhood of the trailing edge of the plate, under the condition that the solution should be matched to the Blasius solution upstream. The value of the skin friction on the plate at any high Reynolds number can be found by use of the numerical table made on the basis of the present solution.
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Shoichi Wakiya
1971 Volume 31 Issue 5 Pages
1581-1587
Published: November 05, 1971
Released on J-STAGE: June 01, 2007
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The exact solution of the Stokes equations for fluid motion around two spheres in contact is given in the most general flow situation. By use of this solution the behavior in shear flow of a doublet composed of two equal-sized spheres in contact is considered. Numerical calculation is carried out, and the motion of the doublet and the rate of energy dissipation are compared with the known case of spheroid.
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Takuma Ishikawa, Takehiko Oguchi
1971 Volume 31 Issue 5 Pages
1588
Published: November 05, 1971
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Haruko Ohmura, Takashi Awaya, Toshiyuki Ishimatsu, Tsutomu Tohei, Take ...
1971 Volume 31 Issue 5 Pages
1589
Published: November 05, 1971
Released on J-STAGE: May 29, 2007
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Yasaburo Yokozawa
1971 Volume 31 Issue 5 Pages
1590
Published: November 05, 1971
Released on J-STAGE: May 29, 2007
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Tomonao Miyadai, Syôhei Miyahara, Teruo Teranishi
1971 Volume 31 Issue 5 Pages
1591
Published: November 05, 1971
Released on J-STAGE: May 29, 2007
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Hironobu Fujii, Nobuaki Shohata, Tetsuhiko Okamoto, Eiji Tatsumoto
1971 Volume 31 Issue 5 Pages
1592
Published: November 05, 1971
Released on J-STAGE: May 29, 2007
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Susumu Matsuo, Shozi Hayashi, Seiichiro Noguchi
1971 Volume 31 Issue 5 Pages
1593-1594
Published: November 05, 1971
Released on J-STAGE: May 29, 2007
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