-
Masatoshi Yamazaki
1980 Volume 49 Issue 5 Pages
1649-1653
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
A new family of stationary axisymmetric, asymptotically flat exact solutions to the Einstein vacuum gravitational fields is reported in a closed form. The family of solutions has four parameters, positive number distortion parameter δ labeling the member of family, rotation parameter μ, reflection parameter λ, and mass parameter
m. When δ=1, the present solution reduces to the Kerr solution. Except the δ=1 solution the present family of solutions contains no event horizon and , when λ≠0, is asymmetric with respect to the reflection at the equatorial plane. Some regularities of solutions are pointed out.
View full abstract
-
Tatsuki Ogino, A. G. Ruggiero
1980 Volume 49 Issue 5 Pages
1654-1664
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Momentum, energy and emittance relaxation processes of the ions have been theoretically studied on the electron cooling in accelerators when the solenoid magnetic field and the space charge of the electron beam are taken into account.
The strong solenoid magnetic field often makes short the energy cooling time by the electron beam with a large transverse energy spread because the transverse electron motion is prohibited over the Larmor radius. On the contrary, the electron space charge makes the energy cooling time long for the sake of electron revolutional velocity. The emittance relaxation time almost agrees with the energy cooling time when the ion velocity spread is less than the electron one. Otherwise, it favourably becomes a little shorter than the energy cooling time due to the cyclic feature of the ion velocity.
View full abstract
-
Vittorio Barci, Andrée Gizon, Jean Gizon, Georges Marguier
1980 Volume 49 Issue 5 Pages
1665-1670
Published: November 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL
RESTRICTED ACCESS
High-spin states in
139Pr have been populated by the
128Te(
14N, 3nγ) reaction and studied using in-beam γ-ray spectroscopic methods. The observed negative-parity level structure based upon the 11⁄2
− isomeric state is different from the decoupled band found in the lighter odd-A praseodymiums and does not exhibit a typical collective behaviour.
View full abstract
-
Shigeo Homma, Shozo Takeno
1980 Volume 49 Issue 5 Pages
1671-1678
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Dynamics and the approximate thermodynamical properties of the classical Ising model in a transverse field (CIMTF) are studied. This is done by elucidating a close correspondence of the CIMTF to a nonlinear lattice field in which each atom, while coupled harmonically with its neighbours, sits on on-site anharmonic potential. It is shown that when the ratio of the Ising interaction to a transverse field-strength exceeds a certain critical value, the on-site potential is of double-well type with saturable nonlinearity. Domain wall modes and magnon modes in continuous one-dimensional CIMTF are studied for both systems to substantiate the correspondence. By exploiting this, a brief study is made on the approximate properties of the free energy and of the dynamical structure factor
S(
k, ω) of longitudinal spin fluctuations of the CIMTF. These quantities are shown to be composed of two contributions, one from domain-wall modes and the other from magnon modes, which manifest themselves as a central peak and side peaks in
S(
k, ω), respectively.
View full abstract
-
Takashi Nakano, Hidetoshi Fukuyama
1980 Volume 49 Issue 5 Pages
1679-1691
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Analytical estimate of the formation energy,
Es, of a soliton is performed for a system of strongly correlated one-dimensional π-electrons coupled to lattice distortions. The problem is first transformed into that of a spin-Peierls systems and then the spin degrees of freedom are represented by the phase Hamiltonian with the help of the boson representation of the spinless fermions. Following Cross and Fisher, parameters in this phase Hamiltonian are adjusted so that the spin wave velocity and the critical exponent of the correlation function agree with the exact results. The soliton solution of the resulting quantum sine-Gordon systems is constructed by the method of Dashen
et al. The result is applied to polyacetylene, where we obtain
Es≈0.3 eV, which is close to the value estimated by Su
et al. for the non-interacting systems.
View full abstract
-
Akihide Oguchi
1980 Volume 49 Issue 5 Pages
1692-1700
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The Ising linear chain with nearest-neighbor interactions of strength
Js and infinite long-range ferromagnetic exponential interactions of strength
Jl was solved exactly in the presence of the external field. The spontaneous magnetization and the susceptibility are obtained. The transition temperature depends on
Js and
Jl. For
Js>0, the model shows the second order phase transion. The specific heat shows both a broad peak and a sharp peak. The value of sharp peak of the specific heat depends on
Js and
Jl. For
Js<0, the properties of the transition agree with those of Nagle model with long-range equivalent-neighbor ferromagnetic interactions. The exact free energy and the long-range order of our model are identical with those of the variational theory of a quasi-one-dimensional model.
View full abstract
-
Hitoshi Sumi
1980 Volume 49 Issue 5 Pages
1701-1712
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
A thermally-activated transition rate
W between two localized electronic states is given which bridges the adiabatic limit, where the two states are mixed well at the activated lattice configuration, and the non-adiabatic limit, where they are not even there. Frequency dispersion of lattice vibrations is fully incorporated which is important to assure irreversibility of the system. Basic quantities are the interaction. energy
J between the two states and the average amplitude
D and velocity \bar
v of thermal fluctuations of the energy difference between adiabatic potentials associated with these states. The semiclassical condition
D>>h\barω is assumed with \barω≡\bar
v⁄
D. The pre-exponential factor of
W is given as a function of γ≡π
J2⁄(h\bar
v) which determines the adiabatic limit for γ>>1 and the non-adiabatic limit for γ<<1. The attempt frequency in
W is given by \barω⁄2π which is written as an average of various normal-mode frequencies.
View full abstract
-
Yasutami Takada
1980 Volume 49 Issue 5 Pages
1713-1721
Published: November 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL
RESTRICTED ACCESS
The effect of the plasmon and/or the acoustic plasmon on superconductivity is investigated in two-subband systems in MOS inversion layers by numerical solutions of the gap equation in the weak-coupling theory of superconductivity, in which the effective interactions are evaluated in the RPA. When the carrier concentration of the system is low, it is shown that the plasmon plays the main role in the superconductivity, while when it is high, the primary contribution comes from the acoustic plasmon. Several criteria to get a high transition temperature are obtained. The Si(100)/SiO
2 system is predicted to show the super-conducting behavior at the temperatures around 1 mK.
View full abstract
-
Izumi Iwasa, Hideji Suzuki
1980 Volume 49 Issue 5 Pages
1722-1730
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Effects of
3He impurities in hcp
4He crystals (20.06 cm
3/mole) on the sound velocity and attenuation are studied at
3He concentrations between 30 ppm and 1% and temperatures down to 0.1 K. In crystals with 1%
3He the velocity change is proportional to
T4 and independent of the sound frequency
Ω⁄2π(=10∼50 MHz). The attenuation below 1 K is proportional to
ΩT4 in accordance with three-phonon processes. No anomalies due to the resonance vibration of dislocations are observed in contrast to pure hcp
4He crystals. In crystals with 30 ppm
3He, amplitude dependences are observed below 0.6 K. The increases in the velocity and the attenuation in a crystal at 10 MHz and 0.3 K are 1.7×10
−3 and 13 dB, respectively, when the amplitude is raised from 10 to 40 dB. It is concluded that the
3He impurities pin the dislocations with a binding energy of about 0.3 K.
View full abstract
-
Fumitaka Matsubara
1980 Volume 49 Issue 5 Pages
1731-1739
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The dispersion relation of excitations and the dynamic susceptibility χ(
q, ω) in the random antiferromagnets Rb
2TxS1−xF
4 and
TxS1−xF
2;
T=Mn or Co and
S=Mg, Zn, Co or Ni, are systematically studied by using a theory developed in I, Some bands of excitations, each of which lies between two single site excitation energies, are obtained in those substances. The line shape of χ(
q, ω) is shown to depend on both the separation of excitation energies and the relative intensity of those excitations which varies with wave vector
q. Our results explain the observed scattering function
St(
q, ω) fairly well in both the line shape and the dispersion relation of the energies at which peaks of
St(
q, ω) occur. The nature of those excitations is also studied by calculating susceptibilities of individual ions.
View full abstract
-
Hironobu Fujii, Yuzo Hashimoto, Tetsuhiko Okamoto
1980 Volume 49 Issue 5 Pages
1740-1746
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Measurements of ac initial susceptibility, magnetization and paramagnetic susceptibility have been made along the principal axes of Tb–Er single crystal alloys. It is found that the magnetic structures of cone, tilted helix, flat helix and basal plane ferromagnet appear at 4.2 K in the sequence of increasing Tb concentration in this system. The tetracritical point showing a coexsistence of CAM, mixed CAM, helix and paramagnet is observed at 87 K for Tb
0.05Er
0.95 alloy. From the analyses of the Néel temperatures and the anisotropic paramagnetic Curie temperatures, the exchange interactions
J(Q),
J(O) and the magnetocrystalline anisotropy
K2para0 in the paramagnetic state were estimated on the basis of the molecular field theory.
View full abstract
-
Nobuo Wada
1980 Volume 49 Issue 5 Pages
1747-1755
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The dependence of the spin configuration in a field induced spin ordered state on the direction of an external magnetic field is studied in β-Ni(NO
2)
2·4H
2O by the measurements of isoentropic
T-
H curve, AC susceptibility χ and specific heat. When the field direction is canted from the
z-axis to the
y-axis, the χ-
H curve is found to have a peak at the central field of the ordered range. And the single peak separates into double peaks by further canting. From a molecular field approximation, these are ascribed to a kind of spin flopping. The antiferromagnetically ordered spins which initially lie along the ±
y-directions in the nonuniaxial crystal field are forced to flop to the ±
x-directions by canting the field direction from the
z-axis to the
y-axis. It is found that the flopped state corresponds to that in the field range between the observed double peaks of the χ-
H curve.
View full abstract
-
Ikuo Yamamoto, Katsunori Iio, Kazukiyo Nagata
1980 Volume 49 Issue 5 Pages
1756-1759
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Magnetic anisotropies of several mangane secrystals have been measured accurately between 77 K and 300 K by using a high sensitive torque-meter. As is predicted by the high temperature expansion theory, the observed magnetic anisotropies vary as the inverse square of the temperature. The crystal field splitting parameters
D and
E have been obtained for each pure magnetically dense sample. In compounds having the octahedron with two water molecules along the axial direction, the splitting parameters
D have been found to be about −0.1 cm
−1, which value is two times or one order of magnitude larger than the typical value of Mn
2+ surrounded by a distorted octahedron composed of six similar ligands. Especially, the value |
D|=0.368 cm
−1 for [(CH
3)
3NH]MnBr
32H
2O is the largest one reported to date.
View full abstract
-
Masashi Takigawa, Hiroshi Yasuoka, Yasutomo J. Uemura, Ryugo S. Hayano ...
1980 Volume 49 Issue 5 Pages
1760-1767
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The temperature dependences of the hyperfine field and the spin-lattice relaxation time
T1 at the interstitial μ
+ sites in the helically ordered state of MnSi have been measured by the
longitudinal μ
+SR technique. The hyperfine field at 4.2 K is found to be −(1.55±0.05) kOe which is 17% smaller than that expected from the hyperfine coupling constant in the paramagnetic state
Ahf=−4.8 kOe/μ
B and the ordered moment of 0.39 μ
B/Mn. The temperature dependence of the relaxation rate 1/
T1 shows an intermediate character between weakly ferromagnetic and antiferromagnetic metals based on the self-consistent renormalization (SCR) theory of spin fluctuations. This fact is in contrast to the observed temperature dependence of 1/
T1 in the paramagnetic state which is in general accord with the prediction of the SCR theory for weakly ferromagnetic metals.
View full abstract
-
Keiji Osaki, Norikiyo Uryû
1980 Volume 49 Issue 5 Pages
1768-1772
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Magnetic ordered states of an
S=1 Ising antiferromagnet with a uniaxial anisotropy
D-term which causes a singlet ground state in the absence of external magnetic field are investigated by the mean field theory. The dependence of the critical temperatures on a uniaxial anisotropy and the
H-
T phase diagrams for various values of anisotropy parameter are calculated. In a certain range of
D-term, there appears a novel kind of phase diagrams where the first-order phase transition, the critical endpoint, and the bicritical endpoint can be seen. The behaviors of free energy of the present system with several phases are also given.
View full abstract
-
Ryugo S. Hayano, Yasutomo J. Uemura, Jun Imazato, Nobuhiko Nishida, Ka ...
1980 Volume 49 Issue 5 Pages
1773-1783
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The static and the dynamic character of the hyperfine field in weak itinerant helimagnet MnSi has been probed by using positive muon spins. The Knight shift has been measured by the transverse-field muon spin rotation method, which revealed a large negative hyperfine field at interstitial sites, even larger compared with other ferromagnetic metals. The hyperfine coupling constant
Ahf has been determined to be −4.8 kOe/μ
B. The divergence of the muon spin-lattice relaxation rate near magnetic ordering has been observed for the first time by using the longitudinal-field muon spin relaxation method. The observed temperature dependence was found to be in agreement with the prediction of the self-consistent renormalization theory of itinerant electron spin fluctuations developed by Moriya and his collaborators.
View full abstract
-
Katsutoshi Iwahashi, Yoshika Masuda
1980 Volume 49 Issue 5 Pages
1784-1789
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Using the spin Hamiltonian, in which interactions up to third neighbors and two kinds of large planar and folded cyclic four spin exchange terms were taken into account, we calculated the resonance frequencies of the nuclear antiferromagnetic resonance in solid
3He observed recently by Osheroff, Cross and Fisher. The typical examples of exchange integrals with which previous experiments can be explained and the corresponding physical quantities are shown.
View full abstract
-
Yoshiro Kakehashi
1980 Volume 49 Issue 5 Pages
1790-1798
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The relation of anomalous volume expansion of Cu–Mn with concentration is elucidated on the basis of the virial theorem and the electronic structure which is calculated with use of the CPA. The origin of the volume expansion is the loss of the bonding energy due to the growth of the magnitude of the Mn local magnetic moment with decreasing Mn concentration. In connection with this problem, it is found that the magnetic pressure is approximately equal to a linear combination of squares of local magnetic moments, which gives a justification for the empirical formula in the magnetovolume effect. The bulk modulus of Cu–Mn and the
P-
Y relation of γ Mn are also calculated.
View full abstract
-
Asako Kawamori, Kensho Sagisawa
1980 Volume 49 Issue 5 Pages
1799-1805
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The temperature dependent ESR linewidth of the single crystal of WBP has been measured between 52.5 and 300 K in the X-band. The second moment is calculated using the crystal structure data and taking into consideration the spin delocalization over the TMPD
+ radical. Below the transition temperature, 190 K, the calculation based on the model of interacting four radicals in two dimers gives the second moment varying with temperature nearly as a linear function of the population of dimers in triplet state. The angular dependence of the experimental halfwidth agrees with the calculated one at 300 and 130 K. The effective exchange frequency which narrows the line is derived using Anderson’s narrowing formula under the assumption of 3-dimensional and isotropic exchange interaction. The mechanism for the effective exchange frequency us discussed.
View full abstract
-
Takeshi Kambara
1980 Volume 49 Issue 5 Pages
1806-1811
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Sorai
et al. (Chem. Phys.
18 (1976) 199) observed that the spin transition temperature in [Fe
xZn
1−x(2-pic)
3]Cl
2·C
2H
5OH varies linearly with iron concentration and the slope of the temperature dependence curve of the high-spin content becomes less steep with decreasing concentration. This dilution effect on the (
Remark: Graphics omitted.) transition is studied on the basis of the ligand field theory by taking account of the coupling between
d electrons of iron and a lattice strain. The calculated temperature dependence of the high-spin content for various iron concentration reproduces the essential features of the observed results including the linear dependence of the spin transition temperature on the concentration.
View full abstract
-
Susumu Katano, Nobuo Mori
1980 Volume 49 Issue 5 Pages
1812-1819
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
It has been reported that the effect of pressure on the resistance minimum is anomalously large in antiferromagnetic
Cr–Fe and
Cr–Co alloys. These experimental results are analyzed on the basis of the Kondo effect, and the Kondo temperature and the spin resistivity are estimated. The magnitude of the spin resistivity is found to depend strongly on both the Néel temperature and the Kondo temperature, and it can be explained well by applying the theory of the magnetoresistance in the Kondo effect. The properties of local moments on Fe and Co atoms are intimately related to the magnetic state of the alloy and these characteristic behaviors are also discussed briefly from the viewpoint of the Kondo effect.
View full abstract
-
Atsushi Fujimori, Fujio Minami, Takashi Akahane, Nobuo Tsuda
1980 Volume 49 Issue 5 Pages
1820-1823
Published: November 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL
RESTRICTED ACCESS
X-ray and ultraviolet photoemission spectroscopy (XPS and UPS) measurements are reported for ReO
3. Difference between the XPS and UPS spectra has revealed O 2
p-derived non-bonding levels and Re 5
d-O 2
p bonding levels, confirming covalency effects in ReO
3. A self-consistent-field-Xα-scattered-wave calculation on a ReO
6 cluster is presented and is compared with experiment. Effects of Madelung potential on orbital energies of the cluster are discussed with relation to covalency.
View full abstract
-
Shuichi Otake, Masayuki Momiuchi, Naoshi Matsuno
1980 Volume 49 Issue 5 Pages
1824-1828
Published: November 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL
RESTRICTED ACCESS
The magnetic susceptibility of bismuth single crystals is measured in the trigonal-binary plane over a wide temperature range from 90 K to 540 K. Moreover, we get a function to express the observed values at any temperature, assuming that the temperature dependence of the energy gap dominates the susceptibility of bismuth. All coefficients of this function are determined by using a feast squares fitting method. Then we can evaluate the energy gap at any temperature; for example, the values of energy gaps at 0 K are 18 meV and 193 meV at the L-point and at the T-point in the Brillouin zone, respectively. They are nearly compatible with other experimental results.
View full abstract
-
Yoshihiro Ohmura, Koji Ishikawa
1980 Volume 49 Issue 5 Pages
1829-1837
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Anomalous spectral densities near threshold for soft X-ray emission and absorption in metals due to the effect of the hole potential are calculated with the use of the generalized power law (GPL) found by Mizuno, Ishikawa and Ohmura and shown graphically. A formula of spectral densities in the presence of the gradient to the transition density of states (TDOS) is proposed on the basis of GPL. The result illustrates absence of the anomaly in
K absorption spectra on Li in agreement with the observation by Petersen. The result is in fair agreement with that of experiments analyzed by Neddermeyer in which the same exponent is obtained for
L emission and absorption spectra of Mg and Al although TDOS is quite different for emission and absorption.
View full abstract
-
Yoichi Takaoka, Kazuko Motizuki
1980 Volume 49 Issue 5 Pages
1838-1844
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Phonon dispersion curves for the high temperature phase of a layer compound 1
T-TiSe
2, which reveals a second order structural phase transition at
Tc=200 K, are calculated using the rigid ion model and the shell model, The calculated phonon dispersion curves, especially with the shell model, are in good agreement with the observation with regard to their gross features. In particular, the calculated dispersion curve for acoustic phonons propagating in the layer and polarized perpendicular to the layer shows an upward bend as this is observed. However, the observed dip at the
L point cannot be reproduced. with our models in which only central two-body forces are assumed; the
L point corresponds to the wave vector of the observed lattice distortion. The results are discussed in connection with other possible effects.
View full abstract
-
Yositaka Onodera
1980 Volume 49 Issue 5 Pages
1845-1850
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
In the existing theory of Wannier exciton, the dependence of longitudinal-transverse splitting on exciton wave vector
k is understood to arise from the dipole-dipole interaction. A theory is developed which, on the basis of the standard
k·
p perturbation theory, yields a much stronger
k-dependence of the splitting, accounting for the recently observed exciton dispersion relation in CuCl.
View full abstract
-
Yasutami Takada, Kunihiro Arai, Naoyuki Uchimura, Yasutada Uemura
1980 Volume 49 Issue 5 Pages
1851-1858
Published: November 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL
RESTRICTED ACCESS
The subband structure of
n-channel inversion layers on InSb its calculated self-consistently in the Hartree approximation. A new method of the effective-mass approach for the nonparabolic band is presented. The splitting, of the spin states caused by the surface potential is calculated to be small and the resonance effect with the hole state in the bulk is found to be very small. The calculated effective masses of the occupied subbands at the Fermi level agree quite well with those measured by Daerr
et al. for a wide range of the carrier concentration.
View full abstract
-
Kitomi Tsutsumi, Takashi Sambongi
1980 Volume 49 Issue 5 Pages
1859-1862
Published: November 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL
RESTRICTED ACCESS
The wave vectors
q1 and
q2 of the periodic lattice distortions coupled with the charge-density-waves in NbSe
3 were re-examined by X-ray diffraction. The results of
q1=(0.245±0.007)
b* and
q2=(0.494±0.008)
a*+(0.267±0.007)
b*+0.50
c* were obtained at 11.2 K. Though two inconsistent results have been reported on the
a*-component of the wave vector
q2, it is ascertained that the
a*-component of the wave vector
q2 is 0.50.
View full abstract
-
G. K. Johri, S. K. Srivastava
1980 Volume 49 Issue 5 Pages
1863-1866
Published: November 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL
RESTRICTED ACCESS
Dielectric relaxation studies of chloral and chloral in benzene are done. Thermodynamical parameters, high frequency permittivity and relaxation time due to over all rotation and due to intramolecular group rotation are evaluated. It is concluded that relaxation mechanism is much more affected by surroundings than the trichloro group attached to the one end of the molecule.
View full abstract
-
Seiichi Miyajima, Nobuo Nakamura, Hideaki Chihara
1980 Volume 49 Issue 5 Pages
1867-1873
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Fluorine-19 spin-lattice relaxation time of crystalline K
2SbF
5 was measured at 10.0 and 26.6 MHz between 77 and 397 K. Angular dependence of
T1 was also examined using a single crystal at 298 K. Magnetic dipolar relaxation due to axial reorientation of the square pyramidal ion SbF
52− was observed, its activation energy being 30 kJ mol
−1. A theoretical expression of
T1 due to reorientation of a square pyramidal ion is derived, which is described as a superposition of the two BPP functions with different time constants, τ
c and 2τ
c. Low temperature relaxation behavior was explained in terms of spin diffusion to paramagnetic impurities.
View full abstract
-
Haruyasu Yamashita, Yoshinori Takeuchi, Itaru Tatsuzaki
1980 Volume 49 Issue 5 Pages
1874-1880
Published: November 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL
RESTRICTED ACCESS
Temperature dependences of dielectric constant and spontaneous polarization in triglycine selenate were measured under hydrostatic pressure. Coefficients of power series expansion of the free energy in respect to electric polarization were calculated front the experimental data. It has been found that the coefficient ξ of the fourth power changes its sign from plus to minus near 5 kbar. This indicates that the tricritical point of triglycine selenate exists at ∼40.6°C and ∼5 kbar.
View full abstract
-
Kenji Miyakawa, Toshirou Yagi
1980 Volume 49 Issue 5 Pages
1881-1886
Published: November 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL
RESTRICTED ACCESS
A central peak has been observed in the Brillouin spectra of a triglycine sulfate (TGS) crystal. The observed scattering intensity shows a strong anisotropy; for the case with a wave vector
q parallel to the
c axis (perpendicular to the polar axis) it shows a temperature dependence which resembles closely that of the specific heat
Cp in shape, while for the case of
q parallel to the
b axis (parallel to the polar axis) it is almost independent of temperature. These results are interpreted in terms of the depolarization field effect which causes an anisotropic fluctuations of the polarization. From the analysis of the temperature dependence curve observed in the case of
q parallel to the
c axis, it is concluded that the central peak is attributed to the thermal diffusion mode.
View full abstract
-
Kiyoshi Deguchi, Eiji Nakamura
1980 Volume 49 Issue 5 Pages
1887-1891
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The dielectric constants of KH
2PO
4 along the
c- and
a-axes have been measured precisely in the paraelectric phase at
T−
Tc\lesssim230 K. Slight deviation from the Curie-Weiss law was found for ε
c and ε
a in the range
T−
Tc\lesssim25 K. The deviation can not be explained by the electrostatic dipole-dipole interaction. The short range correlation taken in Slater’s theory of KH
2PO
4 is a possible origin of this deviation.
View full abstract
-
Mitsuo Wada, Hiroyasu Shichi, Akikatsu Sawada, Yoshihiro Ishibashi
1980 Volume 49 Issue 5 Pages
1892-1895
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The Raman scattering spectra and the thermal expansions of chloranil crystal were measured below and above the phase transition point
T0=93.8 K. The index of the transition parameter was obtained from the temperature dependence of the soft mode frequency for 0.08<(
T0−
T)⁄
T0<0.89 as β=0.47±0.05, including within its range the mean-field value 0.5.
View full abstract
-
A. K. Tripathi, H. B. Lal
1980 Volume 49 Issue 5 Pages
1896-1901
Published: November 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL
RESTRICTED ACCESS
The single crystals of Gd
2(MoO
4)
3 and Tb
2(MoO
4)
3 show very similar Electrical Transport properties. Typical d.c. conductivity results in cooling cycle are given in temperature range 650 to 1075 K. Both these solids reveal intrinsic conduction above 880 K. In temperature range 650 to 805 K the conduction arises due to localized impurities. It is expected that some instabilities in the phases of these crystals are effective from 805 to 880 K. Thermo-electric power in both these solids is highly unstable and is too small to be measured properly. The results are discussed using band model and hopping mechanism.
View full abstract
-
Keiichi Kaneto, Shigehiko Sasa, Katsumi Yoshino, Yoshio Inuishi
1980 Volume 49 Issue 5 Pages
1902-1908
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Electrical resistivity, magnetoresistance and their temperature dependences in (SNBr
y)
x are measured for various quantity of
y. By bromination, negative magnetoresistance is enhanced at 4.2 K and also appears even at 77 K, at which temperature negative magnetoresistance is not observed in undoped (SN)
x. These features are remarkable for the samples heavily doped and just after doping, and are abated by pumping bromine from (SNBr
y)
x for a few days. The possible origins for the anomalous negative magnetoresistance are discussed taking the surface state of fiber bundles or crystal due to adsorped bromine into consideration.
View full abstract
-
Kiyokazu Nakagawa, Koji Maeda, Shin Takeuchi
1980 Volume 49 Issue 5 Pages
1909-1915
Published: November 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL
RESTRICTED ACCESS
Dislocation behaviour at room temperature in CdTe is studied in situ by both the transmission electron microscopy (TEM) and the scanning electron microscopy with the cathodoluminescence mode (SEM–CL). The etch-pitting method is also used. It is found by the TEM observation that dislocations cross-slip frequently, though they are often widely dissociated and glide in pairs. The motion of dislocations, including partials, is steady and continuous, indicating that the short range motion is controlled by the Peierls mechanism. Semi-microscopic observations by the SEM–CL and the etch-pitting method showed, however, that dislocations are apt to be immobilized and the deformation proceeds by multiplying new dislocations successively, suggesting that the macroscopic strain-rate is governed by the multiplication rate and the mean free path which is controlled possibly by jog formation by cross slips.
View full abstract
-
Takeshi Nihira, Tadao Iwata
1980 Volume 49 Issue 5 Pages
1916-1919
Published: November 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL
RESTRICTED ACCESS
Phonon scattering by interstitial atoms in graphite has been studied by measuring the
a-axis thermal conductivity of electron-irradiated pyrolytic graphite in the temperature range of 5 to 80 K. The electron irradiation was performed at temperatures around 80 K. The relaxation time of phonon scattering by interstitial atoms is inversely proportional to the phonon frequency; that is, τ
−1=
Bω, where
B=1.1
4×10
−5 for 1 ppm of interstitial atoms. Changes in the elastic constant
c44 due to irradiations have also been determined through the thermal conductivity data analysis.
View full abstract
-
Hiroshi Kurita, Osamu Sakai, Akio Kotani
1980 Volume 49 Issue 5 Pages
1920-1928
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The resonant light scattering of exciton is studied, with particular attention to the coexistence of cascade LO phonon scattering lines, LA phonon scattering structures and luminescence, by using a model system consisting of one exciton band and LO and LA phonons. Including all the higher order exciton-phonon interactions within the ladder approximation combined with the real process approximation, an integral equation for exciton population is derived and solved numerically to give the spectral shape of the emitted light at low temperatures. It is shown how the real and virtual intermediate states contribute to the cascade LO phonon scattering spectrum, and how the broad luminescence band is formed through the accumulation of multiple scatterings of exciton by LA phonons. The effect of the nonradiative decay of exciton on the relative intensity between the Raman and luminescence spectra is also studied.
View full abstract
-
Osamu Sakai, Hiroshi Kurita, Akio Kotani
1980 Volume 49 Issue 5 Pages
1929-1936
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The relaxation process of a photo-generated exciton is studied under conditions including high temperature and small nonradiative damping, where the LO phonon cascade relaxation (LOCR) lines and a broad luminescence coexist in a wide energy range of the light scattering spectrum. To treat this, a simplified balance equation for the exciton distribution function is derived by extending the theory in the preceding paper, and solved numerically. With some further approximations, analytic investigations are also made. According as how LOCR process and the multiple LA scattering process occur during the life time of exciton, the behavior of the distribution function is classified into three types, and from. this view point, a discussion is given on the comparison with experimental observations.
View full abstract
-
Masami Fujita, Kaizo Nakamura, Yoshio Nakai
1980 Volume 49 Issue 5 Pages
1937-1943
Published: November 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL
RESTRICTED ACCESS
Effect of uv-light irradiation on iodine impurities in KCl: I crystal has been investigated. By uv-light irradiation, intensities of absorption and emission bands associated with isolated iodine ions (monomers) diminish, whereas UV emission band at 4.64 eV due to paired iodine ions (dimers) is enhanced. Enhancement of the UV emission band was confirmed also by measuring excitation spectra. These results suggest that uv-light irradiation converts monomers into dimers. Linear dependence of the growth rate of the UV emission band on the concentration of iodine was confirmed experimentally. This ensures that the probability of trapping for moving monomers is proportional to the concentration of iodine. Therefore, it is certain that the iodine ions excited with uv-light move through the lattice of the host crystal.
View full abstract
-
Hirohiko Adachi, Kazuo Taniguchi
1980 Volume 49 Issue 5 Pages
1944-1953
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The discrete variational (DV) Xα cluster method has been applied to study of X-ray
L2,3 and Kβ emission spectra for XO
4n−, XO
3n− and XO
2n− (X=P), S and Cl) anion complexes. Rigorous calculations for the peak energies and the peak intensities have been performed using the wavefunctions of anion clusters and Slater’s transition state concept. Calculated peak energies and intensities are in excellent agreement with observed values. Theoretical spectra reproduce quite well the experimental data. The results show that the cross-transition terms are very important for quantitative discussion of the X-ray emission spectra.
View full abstract
-
Haruo Sugiyama
1980 Volume 49 Issue 5 Pages
1954-1956
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Thickness dependence of the heavy ion nuclear stopping-power has been estimated on the basis of Hvelplund theory of energy loss straggling. The nuclear stopping-power is found to decrease with increasing thickness.
View full abstract
-
Shozo Tsunekawa, Takeshi Kojima
1980 Volume 49 Issue 5 Pages
1957-1964
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The microwave spectrum of the normal hydrazine N
2H
4 is studied in the frequency range extended up to 130 GHz. The eight series of the
Q-branch transition
ΔJ=0,
K=1←0 are observed. It is found that the inversion splitting for the
JK level is expressed by the form ν
inv=16040.2−1.53×
J(
J+1)−25.9
K2 (MHz). The rotational constants are obtained to be
A=143467.6 MHz,
B=24083.0 MHz and
C=24070.1 MHz. The height of the barrier to the internal rotation is determined to be
V2=1240±50 cm
−1 on the assumption of the twofold potential barrier.
View full abstract
-
Shunjiro Shinohara, Hiroshi Toyama
1980 Volume 49 Issue 5 Pages
1965-1973
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The effect of many passive coils on the positional instabilities in tokamaks is numerically investigated in the case of
t<<τ
e (effective skin time of the coils), assuming the rigid shift of the plasma column. In order to make the positional stability region of the decay index broader, the passive coils must be located as close as to the plasma surface with the optimum position. The skin time of the coils is determined mainly by the number, cross section area and the conductivity of the coils. Application of the analysis to two small tokamaks shows the fairly good agreements with the experimental results.
View full abstract
-
Osamu Mitarai, Yoshinobu Kawai, Fujio Kako
1980 Volume 49 Issue 5 Pages
1974-1980
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
The Buneman instability in a magnetic field is studied numerically using the fluid equations. It is shown that the instability due to the anomalous Doppler effect appears in addition to the Buneman instability. The detailed properties of these two instabilities are obtained by solving the dispersion equation.
View full abstract
-
Hiroshi Fujiyama, Yukio Watanabe, Masanori Akazaki
1980 Volume 49 Issue 5 Pages
1981-1987
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
It is experimentally verified that the dominant region of the nonresonant ion-quasimode is 1<ω
0⁄ω
LH<3 (ω
0: pump frequency, ω
LH: lower-hybrid frequency), by controlling the linear Landau damping and the collisional damping of the parametric decay waves by varying neutral gas pressure, and this ion-quasimode have the maximum amplitude at the ratio ω
0⁄ω
LH\simeq\sqrt2. The measured frequency, amplitude, and threshold of the low frequency decay wave are in good agreement with the Porkolab’s theory of the nonresonant ion-quasimode including the effect of electron-neutral collisions.
View full abstract
-
Tsuguhiro Watanabe, Akira Oda, Hitoshi Hojo, Kyoji Nishikawa
1980 Volume 49 Issue 5 Pages
1988-1994
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
Particle orbits in a line-cusp magnetic field in the presence of electrostatic rf-field localized to the maximum magnetic field region are studied numerically under the initial conditions that the particles start from the cusp center along the straight magnetic field. Results show that 1) when the rf-frequency ω is greater than the maximum cylotron frequency ω
c0 and the electric field strength
E is less than a critical value
Ec, the particles are either unconfined or reflected adiabatically depending on whether the initial energy is greater or smaller than the maximum ponderomotive potential
Φm of the rf-field; 2) when ω
c0<ω but
E>
Ec, nonadiabatic reflection occurs in the energy region just below
Φm; and 3) when ω<ω
c0 there always exist three regimes of unconfinement, nonadiabatic reflection and adiabatic reflection depending on the initial energy. The value of
Ec is determined by the condition for occurrence of the Doppler-shifted cyclotron resonance.
View full abstract
-
Akira Yoshizawa
1980 Volume 49 Issue 5 Pages
1995-2003
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
A Galilean-invariant homogeneous-turbulence theory within Eulerian framework is proposed for the study of the small-scale turbulence. Two Galilean-invariant quantities, the one-time velocity covariance and the convection-free response, are chosen as fundamental ones instead of the usual two-time velocity covariance and response. The Direct-Interaction formalism is applied to find governing equations for these two quantities. Using them, Kolmogorov’s law may be derived with the reasonable estimate of Kolmogorov’s constant. This theory is also applied to the evaluation of the Reynolds stresses in the inhomogeneous turbulence with arbitrary mean flows. Results obtained are shown to coincide with those from the previous work (A. Yoshizawa: J. Phys. Soc. Jpn.
46 (1979) 669 and
47 (1979) 1665), apart from a slight change of numerical factors.
View full abstract
-
Akira Yoshizawa, Masayuki Sakiyama
1980 Volume 49 Issue 5 Pages
2004-2008
Published: November 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL
RESTRICTED ACCESS
A statistical analysis is made of the diffusion of a passive scalar in homogeneous turbulence. An Eulerian Galilean-invariant theory is constructed with the convection-free response and the one-time scalar covariance chosen as fundamental physical quantities and with the aid of the
Direct-Interaction formalism. The −5⁄3 power law for the spectrum of scalar covariance is derived in the intertial range, with the reasonable estimate of its proportional constant.
View full abstract