All issues
Volume 49 (1980)
- Issue 6 Pages 2093-
- Issue 5 Pages 1649-
- Issue 4 Pages 1205-
- Issue 3 Pages 847-
- Issue 2 Pages 435-
- Issue 1 Pages 1-
Predecessor
- Proceedings of the Physico-Mathematical Society of Japan. 3rd Series
- Proceedings of the Tokyo Mathematico-Physical Society. 2nd Series
- Tokyo Sugaku-Butsurigakukwai Kiji-Gaiyo
- Tokyo Sugaku-Butsurigakkwai Hokoku
- Tokyo Sugaku-Butsurigaku Kwai Kiji
- Tokyo Sugaku-Butsurigaku Kwai Kiji
- Tokyo Sugaku Kaisya Zasshi
Volume 49, Issue 2
Displaying 1-50 of 69 articles from this issue
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Kouichi Toyoshima, Tsuyoshi Sugimitsu1980 Volume 49 Issue 2 Pages 435-443
Published: August 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL RESTRICTED ACCESSExcitation functions of γ-rays from the 79Br(p, n)79Kr reaction were measured with 2.82- to 3.50-MeV protons, and neutron-γ and γ-γ coincidence spectra were recorded at 5.00 MeV. Angular distributions of some γ rays were also measured with 3.50-MeV protons to determine spins and parities. A level scheme of 79Kr was proposed from detailed analyses of the data. In particular, a previously unknown 5⁄2+ level was identified at 290 keV, and the presence of a 9⁄2+ level at 149 keV was confirmed.View full abstractDownload PDF (992K) -
Kazumasa Miyano, Yoshiaki Kato1980 Volume 49 Issue 2 Pages 444-447
Published: August 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL RESTRICTED ACCESSHalflives of a 12.34-keV level in 133mBa and two levels in 120Sn were measured by means of a delayed coincidence system which was accurately calibrated by use of a standard pulse generator:
18.0±0.4 n sec for the 12.34-keV level in 133Ba,
11.96±0.09 μ sec for the 2482.0-keV level in 120Sn,
5.55±0.03 n sec for the 2284.6-keV level in 120Sn.
The total internal conversion coefficient for the 12.34-keV transition was obtained to be 65±3, which is in agreement with a theoretical value of 71 but conflicts with a previously reported value of 110. The γ-ray transition was found to be retarded by a factor of 93±4 in Moszkowski units.View full abstractDownload PDF (460K) -
K. Andhradev, V. N. Kulkarni, R. G. Kulkarni1980 Volume 49 Issue 2 Pages 448-455
Published: August 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL RESTRICTED ACCESSThe excited states of 141Pr up to 1800 keV were studied by means of Coulomb excitation of 141Pr with protons of energies from 4.0 to 5.5 MeV. The gamma-ray yields and angular distributions were measured with a Ge(Li) detector. The levels in 141Pr at 1348, 1580.3, 1608.4 and 1785 keV were observed in Coulomb excitation for the first time. The results of gamma-ray angular distribution measurements establish spin values of 3/2+, 5/2+, 3/2+, 3/2+ and 1/2+ for the 1126.9, 1292.6, 1348, 1608.4 and 1785 keV levels respectively. The reduced E2 and M1 transition probabilities were determined for the 1126.9, 1292.6, 1348, 1493, 1608.4 and 1785 keV levels. The results were compared with the available theoretical calculations.View full abstractDownload PDF (996K) -
Katsuya Honda, Huzio Nakano, Kiko Nakamura1980 Volume 49 Issue 2 Pages 456-462
Published: August 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL RESTRICTED ACCESSThe elastic constants of the hard sphere crystal near the melting point are investigated. The assumption in Born’s theory that the elastic constant of shear should vanish at the melting point is examined. In place of his theory which cannot be applied to the hard sphere crystal straightforwardly, the effective potential method developed in a previous paper by one of the present authors (K.H.) is employed. The important effect of atomic ordering in long range in the crystal is taken into account. As an effect of fluctuation in this order parameter, certain elastic constants in particular the bulk modulus diverge to minus infinity at a threshold of the specific volume. In spite of difficulty that the Fourier components of the second derivative of interaction potential is indefinite, the velocities of the lattice wave in the limit of long wave length can be obtained.View full abstractDownload PDF (788K) -
Kêitsiro Aizu1980 Volume 49 Issue 2 Pages 463-469
Published: August 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL RESTRICTED ACCESSIn the previous paper [JPSJ 47 (1979) 1773], the checkpoint of positive definiteness and incompatible inequalities was offered and applied to several transitions. In the present paper another checkpoint is offered and applied to the same transitions. This checkpoint does not seek the eigenvalues of the matrix (∂2Ψ⁄∂Qi∂Qj)s of the ferroic in question (where Q1, Q2, ···denote the transition parameters; Ψ the thermodynamic potential function; s “spontaneous”). Instead it compares the second or higher order curvature of the Ψs of the ferroic in question with those of all other maximal-rank ferroics. For all the above-mentioned transitions the present checkpoint is found to give the same incompatible or compatible inequalities and hence the same conclusions on orders as the previous checkpoint gave.View full abstractDownload PDF (844K) -
Yoshihide Kimishima1980 Volume 49 Issue 2 Pages 470-476
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSThe magnetic susceptibility and specific heat were measured for (CH3NH3)2 Cu(ClxBr1−x)4 mixed crystals. The x-T and x-H phase diagrams were given, and the phase change from the antiferromagnetic phase with easy c-axis to the ferromagnetic phase with easy a-axis was clearly shown for the C1ClxBr1−x system at the boundary of x∼0.1. The qualitative arguments were given for the magnetic phase transitions and magnetically ordered states near the boundary of that concentration.View full abstractDownload PDF (800K) -
Yuji Ueda, Minoru Takahashi1980 Volume 49 Issue 2 Pages 477-483
Published: August 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL RESTRICTED ACCESSFe–Ni alloy films with a composition of Invar region were prepared on copper substrates by electrodeposition. The crystal structures and magnetic properties of the films were investigated. The region which formed α phase in the films was different from that shown in the equilibrium phase diagram for bulk samples of Fe–Ni system, that is, the region shifts toward the nickel richer composition. The drop region the magnetization in the electrodeposited film shows a tendency to shift to the nickel richer composition (45 at.%Ni–Fe) corresponding with the shift of the α phase at the film deposition. The magnetic moment at low temperatures in the electrodeposited film decreases more rapidly with the increase of temperature as compared with the result observed in the bulk crystal.View full abstractDownload PDF (1012K) -
Akio Takase, Tadao Kasuya1980 Volume 49 Issue 2 Pages 484-488
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSTransverse magnetoresistances in the screw-, ferro- and fan-phases of MnP have been studied for various samples which have values of the residual resistivity ratio, R.R.R., ranging from 60 to 562. At 4.2 K, the screw-ferro and the screw-fan transition fields increase with increasing R.R.R., tending to constant values of 3.1 kOe and 7.0 kOe, respectively, in the purest limit. Magnetic phase diagrams have been constructed for the lowest and highest purity samples in the temperature and magnetic field plane, the magnetic field being either along the b axis or the c axis. Their difference is attributed to the reduction of the peak height of J(q) with increasing impurity.View full abstractDownload PDF (608K) -
Akio Takase, Tadao Kasuya1980 Volume 49 Issue 2 Pages 489-492
Published: August 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL RESTRICTED ACCESSThe transverse magnetoresistances of high purity single crystals of MnP have been measured at a temperature of 1.5 K in applied magnetic field up to 80 kOe. The magnetoresistance exhibits sharp minima for the magnetic field along the b and c axes, which suggests the existence of cylindrical Fermi surfaces perpendicular to the a axis, in consistency with previous experiments. The Shubnikov-de Haas-like oscillation with a frequency of 1.7×105 G is observed in the a axis resistivity under the b axis magnetic field.View full abstractDownload PDF (476K) -
Yoshio Kitaoka, Hiroshi Yasuoka1980 Volume 49 Issue 2 Pages 493-498
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSThe properties of the spin fluctuations in the typical d-band metal CrB2 have been studied in both the paramagnetic and the ordered states by using the pulsed NMR technique. The temperature dependences of the staggered moment MQ and the nuclear spin-lattice relaxation rate 1⁄T1 of 11B above TN are found to be explained neither from the spin fluctuation theory of weakly antiferromagnetic limit nor from the local moment limit, indicating that CrB2 is an intermediate substance in the magnetic point of view. It could be pointed out however that the observed Curie-Weiss behavior of the uniform susceptibility χu(T) with a large negative Weiss constant (θp\simeq−900 K) is a manifestation of the case where the amplitude of the spin density fluctuations is relatively large, corresponding to strong electron-electron interactions and is in general accord with the recent unified theory of magnetism in narrow band electron systems.View full abstractDownload PDF (852K) -
H. Murrieta S., F. J. López, J. Rubio O., G. Aguilar S.1980 Volume 49 Issue 2 Pages 499-503
Published: August 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL RESTRICTED ACCESSA calculation of the trigonal spin-Hamiltonian parameters for Fe3+ in KZnF3 was performed using Newman’s superposition model and the knowledge of the local arrangement of the fluorine coordinated ligands surrounding the iron ion. It was found that both the sign and the magnitude of the calculated parameters are in good agreement with those previously determined experimentally. Also, an Electron Paramagnetic Resonance (EPR) investigation of Fe3+ in four inequivalent axial sites (trigonal) of KMgF3 was carried out and the spin-Hamiltonian parameters describing the site symmetry were determined for the first time. From this information, an analysis was made, using the superposition model, of the local arrangement around the impurity Fe3+ ion responsible for the observed trigonal EPR spectra.View full abstractDownload PDF (684K) -
Hironobu Ikeda, Tormod Riste, Gen Shirane1980 Volume 49 Issue 2 Pages 504-507
Published: August 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL RESTRICTED ACCESSMagnetic excitations in a two-dimensional random, antiferromagnet Rb2Co0.5Mn0.5F4 are studied by inelastic neutron scattering. Two well-defined bands of excitations with localized nature are observed. These bands show no measurable renormalization up to TN. This implies that each band has a predominantly Co and Mn character but Mn excitations of lower band are significantly affected by Ising nature of Co spins surrounding Mn spins.View full abstractDownload PDF (484K) -
Jun Takeuchi, Hiroyuki Sasakura, Yoshika Masuda1980 Volume 49 Issue 2 Pages 508-513
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSLow temperature specific heat of the itinerant electron antiferromagnetic Cr1−xVx alloys was measured in the temperature range between 1.4 and 5.0 K. The V concentration dependence of the linear specific heat coefficient is interpreted in terms of two contributions, the effect of spin fluctuations and the variation of the density of states at the Fermi level resulting from the antiferromagnetic band gap. This interpretation explains consistently the enhancement of the electrical resistivity in the antiferromagnetic state.View full abstractDownload PDF (660K) -
Masatsugu Suzuki, Kyoko Kato, Hironobu Ikeda1980 Volume 49 Issue 2 Pages 514-520
Published: August 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL RESTRICTED ACCESSUltrasonic attenuation in a two-dimensional Ising-like antiferromagnet Rb2CoF4 has been measured at frequencies from 10 to 150 MHz near the Néel temperature, TN=103.20±0.02 K. Above TN it is found that the critical attenuation α is described by a scaling function, ω1+yfF(ωτ), where ω is an angular frequency of sound wave and τ is a characteristic time of order-parameter fluctuations and is expressed as τ∝t−x using reduced temperature, t=|T⁄TN−1|, with results x=1.20±0.10 and y=0.31±0.03. The dynamic critical exponent is determined as z=x⁄ν=1.21±0.10 when the existing value of ν (=0.99±0.04) is used. The critical attenuation has a maximum below TN which shifts to lower temperature as frequency increases. This behaviour can be explained in terms of the relaxation of order-parameter.View full abstractDownload PDF (832K) -
Shigeru Takagi, Yoshio Kitaoka, Hiroshi Yasuoka, Tsukio Ohtani, Koji K ...1980 Volume 49 Issue 2 Pages 521-527
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSThe microscopic magnetic properties of vanadium “monoxide” VO1.25 have been investigated by 51V NMR at temperatures from 1.2 K to 300 K. Two kinds of resonance corresponding to different electronic states were observed. One comes from the nearly nonmagnetic majority sites and it is concluded from the temperature dependences of both the nuclear relaxation rate and the with of the spin-echo spectrum that VO1.25 orders magnetically below 5 K. At 1.2 K in the ordered state, the other kind of resonance was observed around 200 MHz under zero external field, so the magnetic ordering is ascribed to these small numbers of V3+-like sites. Curie-Weiss type temperature dependence of the susceptibility in the paramagnetic state can also be accounted for by presuming that about 8% of V ions are V3+, with a localized moment of 2 μB. The crystallographical origin of the V3+-like sites is also discussed.View full abstractDownload PDF (1000K) -
Masayuki Shiga, Yoji Nakamura1980 Volume 49 Issue 2 Pages 528-534
Published: August 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL RESTRICTED ACCESSThe Mössbauer spectra of Fe–Cr solid solutions in the concentration range of 60–96 at%Cr were obtained at 5 K. These spectra were analyzed to yield hyperfine field distribution curves which are characterized by two distinct peaks. It has been revealed that an isolated Fe atom has a very small hyperfine field indicating a nonmagnetic character. The profiles of the hyperfine field distribution curves as well as the magnetic properties of the alloys, particularly near the critical concentration for ferromagnetism, are discussed on the basis of the local environment model.View full abstractDownload PDF (804K) -
Akio Kotani, Isao Harada1980 Volume 49 Issue 2 Pages 535-544
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSMean-field study of the Peierls instability is made at zero temperature with the electron occupation number varied over a wide range between half-occupancy and nearly zero-occupancy. Total energy of the system, order parameters and the lattice displacement pattern are calculated by taking account of all the accompanying harmonics. The lowering of the total energy per atom is shown to be very large in the neighborhood of the half- and 1/15-occupancies. The amplitudes of harmonics increase drastically as the electron number approaches the zero-occupancy. The spin-Peierls transition is also studied with an XY model. Although the effect of magnetic field on the spin-Peierls system has a close similarity to that of the electron number variation on the Peierls system, an important difference between them is pointed out on the pinning of a dimerized state.View full abstractDownload PDF (1096K) -
Kimio Adachi, Norio Achiwa, Mamoru Mekata1980 Volume 49 Issue 2 Pages 545-553
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSNeutron diffraction measurements were made on single crystals of CsCuCl3. The sense of Cu2+ ion helix was found from nuclear reflections to be predominantly right-handed. The magnetic reflection data could be interpreted satisfactorily by considering a triangular spin structure of helically modulated ferromagnetic chains: The magnetic moments lie in the c-plane and rotate by 5.1±0.1° along the chain or the c-axis, while the moments rotate by 120° in the c-plane. The magnitude of the magnetic moment is 0.58±0.01 μB at 4.2 K. The critical exponent of the magnetization, β was found to be 0.358±0.015 around the Néel temperature, 10.70±0.05 K. We present a model that the helical modulation along the c-axis is caused by the antisymmetric exchange (Dzyaloshinsky-Moriya) interaction characteristic of the crystal symmetry of CsCuCl3. The model predicts a right-handed magnetic helix in the present case.View full abstractDownload PDF (1148K) -
Michio Midorikawa, Yoshihiro Ishibashi, Shin-ichi Nakashima, Akiyoshi ...1980 Volume 49 Issue 2 Pages 554-556
Published: August 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL RESTRICTED ACCESSThe p-T phase diagram of Hg2Cl2 was obtained through the measurements of strains carried out under various pressures up to about 5 kbar. Pressure derivative, dTc⁄dp, for the tetragonal-orthorhombic transition was found to be 44 K/kbar.View full abstractDownload PDF (320K) -
Yoshio Ishizawa, Takaho Tanaka, Eisuke Bannai1980 Volume 49 Issue 2 Pages 557-561
Published: August 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL RESTRICTED ACCESSThe transverse magnetoresistance of LaB6, single crystals has been studied at 1.5 K in magnetic fields up to 60 kOe. Open orbits along [110] and [001] are observed for H along θ=27° (from [001]) in the (1\bar10) plane and at most field directions (except near θ=0°) in the (010) plane, respectively. The [001] direction is a singular field direction. The low frequency oscillations with the order of 104 gauss are superimposed on the monotonic magnetoresistance. Present results are consistent with a multiply-connected Fermi surface model proposed already from de Haas-van Alphen experiments.View full abstractDownload PDF (700K) -
Toshikazu Hirose1980 Volume 49 Issue 2 Pages 562-568
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSSemiconducting WO3 with the donor electrons trapped in oxygen vacancies shows so-called ‘semiconductor-metal transition’ at the triclinic-monoclinic (I) phase transition temperature at about 17°C. Resistivity discontinuities as large as a factor 102 have been observed at the monoclinic: (II)-triclinic phase transition at about −40°C.
The semiconductor-metal transition is interpreted by the consideration that the energy gap between the t2g orbitals of 5d1 conduction electrons and the donor level are enlarged by the crystalline distortions due to the condensations of the soft phonon modes. The resistivity discontinuities are interpreted as due to the different energy gaps in the monoclinic (II) and triclinic phases.
The essential difference between WO3 and ReO3 having the same crystal structure is discussed.View full abstractDownload PDF (808K) -
Shigeru Tanaka, Koichi Mizushima, Shuichi Iida1980 Volume 49 Issue 2 Pages 569-572
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSThe electron spin-lattice relaxation time T1 of (3d)4 type ion, Mn3+, in rutile was measured from 1.7 K up to 7 K by the pulse saturation recovery method. It was concluded that, in a liquid He temperature region, T1 was determined by the Orbach process via three excited levels.
The anisotropy of T1 was observed at 4.2 K, although T1 by the simple Orbach process is expected to be independent of the direction of static magnetic field. In order to understand this result, we presume that the relaxation of Mn3+ ion in TiO2 is phonon-bottlenecked, suggesting stronger coupling of Mn3+ spin with the lattice than the case of Fe3+, Mn4+ or Cr3+ ions.View full abstractDownload PDF (520K) -
Seizo Morita, Shuzo Takano, Nobuo Mikoshiba1980 Volume 49 Issue 2 Pages 573-577
Published: August 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL RESTRICTED ACCESSWe have reexamined “photo-induced magnetophonon resonanc” (nhωC=hωLO) in n-InSb previously observed by a part of our group by measuring its dependence on the photon energy with a tunable CO2 laser and have proved that this resonance is three-LO-phonon assisted cyclotron resonance. This resonance occurs at the magnetic field of hω=3hωLO+En,s, −E0,↓ and appears as minima in the photoresponse. We also examined the amplitudes and the damping constants of this resonance by the method of magnetic derivative of photoresponse. As a result, this resonance were divided into three series with different amplitudes and damping constants.View full abstractDownload PDF (592K) -
Tetsuro Saso, Tadao Kasuya1980 Volume 49 Issue 2 Pages 578-588
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSResistivities and Hall coefficients of unstressed and uniaxially saturation-stressed samples of heavily antimony-doped germanium in the metallic concentration range are investigated by the degenerate electron gas model with impurity scattering. The effect of anisotropic effective mass is investigated, firstly by the variational method, and secondly by solving the Boltzmann equation directly in a numerical method. The anisotropy of screened impurity potential is fully taken into account within the linear screening theory. The effect of finite electron life time is studied by a simplified coherent potential approximation. By these effects, in addition to the effect of the nonlinear screening and many-body interaction investigated in the authors’ previous paper, the agreement with experiments on the unstressed samples is much improved and a good agreement is obtained on the saturation-stressed samples.View full abstractDownload PDF (1320K) -
Contribution of the Imaginary Part of Photoelastic Constants to Resonant Brillouin Scattering in CdSKenji Wasa, Toshihide Akiyama, Kazuo Tsubouchi, Masamichi Yamanishi, N ...1980 Volume 49 Issue 2 Pages 589-592
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSA deep but finite minimum in the dispersion of the Brillouin scattering cross section has been found in the wavelength region of the resonant cancellation at 562.4 nm (T=300 K) in CdS. This minimum is interpreted as arising from the contribution of the imaginary part of photoelastic constant P66, whose existence has been overlooked so far. The lifetime broadening is introduced to obtain the imaginary part by replacing the photon energy hω with hω+iΓ (Γ: damping energy) in the piezobirefringence theory. The damping energy is found to be Γ=0.5 meV at 300 K from the best fitting of the theoretical curve to the experimental results.View full abstractDownload PDF (532K) -
Toshio Osaka, Yasuharu Makita, Kazuo Gesi1980 Volume 49 Issue 2 Pages 593-598
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSDielectric constant along the direction perpendicular to the (001) plane in crystals of {(NH4)3H(SO4)2}1−x {(ND4)3D(SO4)2}x system was measured for various x values in a temperature range from liquid nitrogen temperature to room temperature. The crystal has two ferroelectric phases in the range of x≥0.9 and one ferroelectric phase in the range of x<0.9. It is found from the phase diagram that the normal crystal (NH4)3H(SO4)2 undergoes a ferroelectric phase transition at about −210°C, besides four non-ferroelectric transitions reported previously. Saturated value of spontaneous polarization estimated as a function of x is about 1.4 μC/cm2 for (NH4)3H(SO4)2 and about 2.5 μC/cm2 for (ND4)3D(SO4)2 in the lowest ferroelectric phase. There is practically no isotope effect on non-ferroelectric transitions, in contrast with large isotope effect on ferroelectric ones.View full abstractDownload PDF (744K) -
Masakiyo Horioka, Ryuji Abe, Tsutomu Naka1980 Volume 49 Issue 2 Pages 599-607
Published: August 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL RESTRICTED ACCESSThe complex dielectric constants of the mixed crystals Na[K1−x(NH4)x] C4H4O6·4H2O (x=0.25, 0.41, 0.63, 0.70, 0.80) have been measured in a frequency range from 3.8 MHz to 24 GHz in the ferroelectric and paraelectric regions. It was found that for the sample of x=0.25, the dielectric dispersion occuring along the ferroelectric a-axis was of monodispersive Debye-type and the molecular field approximation was nearly satisfied, whereas for the samples of larger x it became polydispersive and obeyed the Cole-Cole dispersion low. The tendency to become polydispersive was evident with the increase of x and for the sample of x=0.8, the parameter β, which is a measure of polydispersion, was 0.77. The mechanism of dielectric relaxation in the mixed crystal is discussed in relation to the present experimental result.View full abstractDownload PDF (1172K) -
Bijay Krishna Chaudhuri, Tooru Atake, Suvra Ganguli, Hideaki Chihara1980 Volume 49 Issue 2 Pages 608-618
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSStatistical Green’s function theory has been successfully applied to study the ferroelectric phase transitions in the Rochelle Salt and its deuterated form with two sub-lattice pseudo-spin model containing spin-phonon interaction terms. The Blinc-de Gennes model parameters have been calculated for both of the salts. A phenomenological explanation of the isotope and the impurity dependence of the transition temperatures has also been sought from our calculations. The origin of non-logarithmic behaviour of the heat capacity has been attributed to the strong proton-phonon and anharmonic interactions. Finally, renormalized phonon frequency and the temperature dependence of the soft mode frequency have been studied theoretically. The present study suggests that phase transitions for the Rochelle Salt and its deuterated variety can be understood by a displacive mechanism.View full abstractDownload PDF (1328K) -
Yoshihiro Ishibashi1980 Volume 49 Issue 2 Pages 619-623
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSA tentative interpretation of the isomorphous transition in SnCl2·2H2O crystal is shown. The Landau-type thermodynamic potential is proposed, which contains odd-order terms in sublattice polarization in addition to those commonly allowed. Temperature dependences of electric susceptibility and specific heat are derived and discussed. Appearance of the critical point is mentioned.View full abstractDownload PDF (596K) -
Atsuo Hattori, Mitsuo Wada, Akikatsu Sawada, Yoshihiro Ishibashi1980 Volume 49 Issue 2 Pages 624-627
Published: August 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL RESTRICTED ACCESSThe Raman scattering spectra of C6H5NH3Br have been studied above and below the ferroelastic phase transition temperature Tc=27°C. In contradiction with the previous inference based on X-ray diffuse scattering experiments that a transverse optical phonon as well as the transverse acoustic mode becomes unstable at the transition, no soft optical phonon was observed in the present Raman experiment.View full abstractDownload PDF (412K) -
Arisato Kawabata1980 Volume 49 Issue 2 Pages 628-637
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSTheory of negative magnetoresistance proposed recently by the author is presented in details and is applied to heavily doped semiconductors. Experiments on n-type GaAs are semi-quantitatively explained. The theory is extended to the case of anisotropic systems and is applied to Ge and Si. Quantitative agreements with experiment are obtained on the anisotropy of magnetoresistance Δρ in Ge. Square root dependence of Δρ out the magnitude of the magnetic field observed in Ge agrees with the prediction of the theory. As for the magnitude of Δρ in Ge and Si, discrepancies between the theory and experiments are rather large.View full abstractDownload PDF (1116K) -
Kazuo Hattori1980 Volume 49 Issue 2 Pages 638-643
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSElectrical conductivity is calculated in the Hubbard model for a disordered chain. The intra-site Coulomb repulsion is assumed to be sufficiently strong, and the electron-transfer term is treated as a perturbation. The interaction between electrons and intra-site vibrations is taken into account by two types of coupling terms. The effects of this interaction on the conductivity are discussed.View full abstractDownload PDF (620K) -
Hidetoshi Fukuyama1980 Volume 49 Issue 2 Pages 644-648
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSThe Hall conductivity, σxy, is evaluated in two-dimensional random systems to the leading order of singular behavior at low frequency, ω. At weak magnetic field the result is σxy=σxy0 [1−1⁄πεFτ ln 1⁄ωτ] where σxy0, εF and τ are ordinary Hall conductivity, the Fermi energy, and the relaxation time due to impurity scattering, respectively. This result together with that for σxx indicates that the effective carrier number deduced from the Hall coefficient does not contain leading singular terms and that only the relaxation time is logarithmically reduced.View full abstractDownload PDF (472K) -
Hidetoshi Fukuyama1980 Volume 49 Issue 2 Pages 649-651
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSIntervalley impurity scattering is shown to reduce the prefactor of the logarithmic term of conductivity in two-dimensional random systems. The effective carrier number deduced from the Hall coefficient, however, does not contain logarithmic term as in a single valley system.View full abstractDownload PDF (340K) -
Syozo Kubo, Tsuneyoshi Tsuru1980 Volume 49 Issue 2 Pages 652-656
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSTransition of a radiation field is theoretically studied in a radiation layer. A steady one-dimensional problem of radiative heat transfer is considered through a gray absorbing, emitting and scattering medium in a semi-infinite space bounded by a plate, which is gray and semitransparent. Through the plate, a beam is imposed perpendicularly in addition to the isotropic emission from the plate. The heat flux in a deep region is maintained to a constant value. The scattering model is the Rayleigh model. The radiation intensity is obtained as a function of position and direction. The results show the transition of the radiation field from a strongly anisotropic field in the neighbourhood of the boundary to the field in a deep region where a weak anisotropic field is caused by the constant heat flux. The effect of the anisotropic scattering is very weak and effectively negligible.View full abstractDownload PDF (532K) -
Atsuo Matsui, Hitoshi Nishimura1980 Volume 49 Issue 2 Pages 657-663
Published: August 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL RESTRICTED ACCESSThe resonance luminescence due to radiative annihilation of free excitons in Pyrene has been observed. The luminescence band is located at 376 nm (F) at room temperature and is quite distinctive from so-called excimer luminescence band located at 450 nm. There is a potential barrier between the free exciton state and the excimer state which is located 540 cm−1 (66 meV) lower in energy with respect to the free exciton state. The luminescence decays exponentially with a life time of 180 nsec for both free excitons and excimers at 282 K. Discussion is given to explain free exciton creation and luminescence processes in terms of thermal equilibrium established between free excitons and excimers. The excimer is recognized as the self trapped exciton.View full abstractDownload PDF (816K) -
Shoji Masunaga1980 Volume 49 Issue 2 Pages 664-670
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSPressure dependences of absorption and emission spectra of impurities in solids are calculated with a one dimensional configuration-coordinate model considering pressure-dependent linear coupling coefficient and force constants which arise through anharmonic terms of the adiabatic potential energies. It is shown that the pressure-dependent force constants play an important role in the understanding of the pressure effects on the peak positions, band-widths and Huang-Rhys parameters.View full abstractDownload PDF (676K) -
Masatsugu Suzuki, Hironobu Ikeda, Hiroyoshi Suematsu, Yasuo Endoh, Hir ...1980 Volume 49 Issue 2 Pages 671-677
Published: August 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL RESTRICTED ACCESSA neutron elastic scattering measurement has been performed on C24Rb at temperatures between 106 K and 165 K. The observed extinction rule of the diffraction can be explained on the basis of a simple model: Rb layers form a triangular lattice with fundamental wave vector |GR0|=1.20 Å−1, which is modulated by the graphite layers. The modulation is described by a static distortion wave, which manifests itself in the appearance of a satellite peak at |GR0−G0|=1.78 Å−1, for example, where |G0|=2.95 Å−1 is the fundamental in-plane wave vector of graphite. This model leads to a prediction that the Rb layer is rotated relative to the graphite layer by ∼9°.View full abstractDownload PDF (720K) -
Takashi Sakuma, Sadao Hoshino1980 Volume 49 Issue 2 Pages 678-683
Published: August 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL RESTRICTED ACCESSThe ordered phase concerning the Ag distribution of a superionic conductor Ag3SBr was discovered below 128 K. The transition heat and the entropy change were measured to be 0.23 kcal/mol and 1.77 cal/mol·deg respectively. The transition is of the first order but is close to the second order one. The crystal structures of the newly found γ-phase and the room temperature β-phase were studied by a least-squares method using X-ray and neutron diffraction data. The structures of the γ-phase and the β-phase of Ag3SBr were similar to those of Phase III and Phase I of CsPbCl3 respectively. The space group of the γ-phase may be D2h17-Cmcm. The lattice constants of the γ-phase were measured to be a(\simeqb)=9.423±0.008 A and c=9.711±0.009 A at 118 K. The nature of the phase transition of Ag3SBr is discussed in connection with those of Ag3SI and CsPbCl3.View full abstractDownload PDF (744K) -
Ayahiko Ichimiya, Kyozaburo Kambe, Gunter Lehmpfuhl1980 Volume 49 Issue 2 Pages 684-688
Published: August 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL RESTRICTED ACCESSThe angular dependence of the specular spot intensity reflected from a ZnS (110) surface has been analyzed by using Bethe’s: dynamical theory. Many-beam calculations have been carried out with simple surface potential models. The calculations showed that the angular dependence of the intensity changed very sensitively with the surface potential shape at the surface state resonance positions. One of the models was in very good qualitative agreement with the present experimental result.View full abstractDownload PDF (748K) -
Kunihiko Morimoto1980 Volume 49 Issue 2 Pages 689-695
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSIn order to calculate the spin-lattice relaxation time T1 of protons of CH3-group at low temperature, a model of relaxation which is available when γHLτr>>1 has been proposed, where HL is the local dipolar field and τr is the correlation time. Present calculation of T1 is closely related to that of the absorption spectra of proton spins in which the non-secular part of the dipolar interaction is included. It is shown that the spin-lattice relaxation is caused by the non-magnetic Orbach process between the ground and first exited torsional states. Present model predicts that when the tunneling resonance occurs, T1 is given by T1\simeqτr, which is different from the result of the second-order calculation and the Haupt theory. The absorption spectra at the tunneling resonance has also been calculated. The measurement of T1 and absorption spectra at the tunneling resonance is useful to determine the precise value of the tunneling splitting.View full abstractDownload PDF (812K) -
Naoki Yasumaru, Satoshi Oku, Takashi Fujimoto, Kuniya Fukuda1980 Volume 49 Issue 2 Pages 696-703
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSBy observing the time-resolved fluorescence following the laser excitation of a helium level in a discharge plasma, the authors have determined the excitation transfer rate coefficients among the n=3 levels due to atomic and electronic collisions. The result in the form of the thermally averaged cross section is: for 31P→31D ⟨σatom⟩=(1.9±0.4)×10−15 cm2 and ⟨σelec.⟩=(2.4±1.2)×10−13 cm2; for 33D→33P ⟨σatom⟩=(5.3±1.2)×10−17 cm2 and ⟨σelec.⟩=(0.9±0.4)×10−13 cm2. The cross sections for atomic collisions are in reasonably good agreement with other experimental and theoretical data, but the cross sections for electronic collisions are larger than the earlier experimental data by two orders and are extremely good agreement with the recent calculations.View full abstractDownload PDF (1092K) -
Kazuhiro Nozaki1980 Volume 49 Issue 2 Pages 704-709
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSNonlinear magnetostatic modes and twisting modes are shown to be described by the Modified K-dV equation and the K-dV equation respectively. The magnetic islands produced by those modes behave like solitons and are accompanied by electrostatic convective cells.View full abstractDownload PDF (620K) -
Yasuyuki Nogi, Hiroaki Ogura, Yukio Osanai, Katsunori Saito, Shouichi ...1980 Volume 49 Issue 2 Pages 710-716
Published: August 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL RESTRICTED ACCESSProduction of a spheromak configuration is attempted by using a theta pinch combined with a z-discharge. A loop current which is formed by a z-discharge current flowing in the plasma and reversing on its surface generates a toroidal field in the spheromak. Mechanism of the current reversal is explained from toroidal flux conservation in the plasma during implosion phase of the theta pinch. It is found that the reverse ratio is controlled in actual experiments by an external inductance of the z-discharge circuit, a length and a compression ratio of the plasma. Experiments show that 70% reversal of the z-current is easily realized using a conventional theta pinch.View full abstractDownload PDF (668K) -
Takashi Abe, Keishiro Niu1980 Volume 49 Issue 2 Pages 717-724
Published: August 15, 1980
Released on J-STAGE: May 29, 2007
JOURNAL RESTRICTED ACCESSThe stability of the electron plasma with stresses (body stress or shear stress) is analysed against the electromagnetic mode. There are two kinds of modes; one is purely transversal, and another is transverse-longitudinal coupled mode. These modes show the instability of the Weibel type when stresses exceed thresholds. It is shown that this instability takes place in the target plasma in inertial confinement fusion, and causes an anomalous viscosity.View full abstractDownload PDF (856K) -
Takashi Abe, Keishiro Niu1980 Volume 49 Issue 2 Pages 725-729
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSUsing the results obtained in Part 1 on the instabilities in an electron plasma with stresses, the stationary turbulence arisen from the instabilities and the resultant viscosity are analysed on the basis of a nonlinear theory similar to Dupree’s one. In the analysis, the broadening of resonance plays an important role in the saturation of fluctuations. It is shown that the viscosity in the target plasma of inertial confinement fusion is much reduced in comparison to the classical one, by this anomalous transport mechanism.View full abstractDownload PDF (632K) -
Kenji Yamamoto1980 Volume 49 Issue 2 Pages 730-740
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSSpectral line shifts for a few low-lying allowed transitions of ionized helium in the thermal plasma are investigated from a view-point of the quantum scattering approach based on the impact approximation with the aid of the R-matrix method. The short-time fluctuations of a field due to electrons close to the radiating ion are fully taken into account and are expressed in terms of transition matrices for the lowest six states of the radiator. It turns out that the line center of Lyman-β undergoes only a small red shift whereas those of each component of Balmer-α undergo remarkable red shifts. All the level shifts are derived from close collisions with the perturbers incident upon the internal region of the configuration space describing the scattered electron and the target. The results are discussed and compared with experimental shifts as well as with existing theoretical results for the line shift.View full abstractDownload PDF (1452K) -
Tuguhiro Watanabe, Toshio Tange, Kyoji Nishikawa1980 Volume 49 Issue 2 Pages 741-746
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSUsing a model equation which describes the wave propagation with a step like localized energy source, we examined the criterion for absolute instability of the wave localized to the source region. Both the case of an optical mode with a step like localized potential well or anti well and the case of an acoustic mode with zero potential are investigated. It is shown that the absolute instability can occur either when the wave is trapped in the localized source region, or when the wave is untrapped but the source strength exceeds a threshold value. For the case of the acoustic mode, the threshold of the local growth rate is given by the convection damping rate, while for the case of the optical mode with anti-well potential, it first increases proportionally to the potential height, but soon saturates to 1.2 times the local convection damping rate.View full abstractDownload PDF (560K) -
Jun-ichi Sakai, Tutomu Kawata1980 Volume 49 Issue 2 Pages 747-752
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSBasic equations describing a macroscopic behaviour of ultra-relativistic plasma (T>>mc2) are formulated in a covariant form. Waves in an electron-positron plasma are investigated in a frame of two-fluid model equation. Dispersion relations for electrostatic wave, electromagnetic wave and Alfven wave propagating parallel to a constant magnetic field are shown. In the case that both electron and positron gases have same temperature, there does not exist the slow mode which corresponds to the ion acoustic wave. Right and left circular polarized waves propagate with the same dispersion relation which is different from one of the non-relativistic electron-ion plasma.View full abstractDownload PDF (520K) -
Jun-ichi Sakai, Tutomu Kawata1980 Volume 49 Issue 2 Pages 753-758
Published: August 15, 1980
Released on J-STAGE: June 01, 2007
JOURNAL RESTRICTED ACCESSNonlinear Alfven wave propagating parallel to a constant magnetic field in an ultra-relativistic electron-positron plasma is investigated in a frame of covariant two-fluid model equation. It is shown that the nonlinear evolution of circular polarized Alfven wave is described by
(Remark: Graphics omitted.),
where B is the wave amplitude. Some stationary solutions (bright soliton, kink solution, spiky soliton with rapid phase rotation) are discussed.View full abstractDownload PDF (488K)