Journal of the Physical Society of Japan
Online ISSN : 1347-4073
Print ISSN : 0031-9015
ISSN-L : 0031-9015
Volume 56, Issue 5
Displaying 1-41 of 41 articles from this issue
  • Kiyomi Okamoto
    1987 Volume 56 Issue 5 Pages 1627-1630
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    We conjecture the temperature dependence of the correlation length ξ of the spin-spin correlation function ⟨SizSjz⟩ in spin-1/2 alternating Heisenberg-XY antiferromagnets. We use the phase representation and the self-consistent harmonic approximation to evaluate ⟨SizSjz⟩. The correlation length ξ as a function of the temperature has a peak at T∼εg, where εg is the energy gap between the ground state and the first excited state.
    Download PDF (452K)
  • Akihiko Toda, Hiroshi Kiho
    1987 Volume 56 Issue 5 Pages 1631-1634
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    We have succeeded in obtaining the nucleation rate and velocity of the travelling of steps from the nucleation and growth processes of polymer crystallization, utilizing the enhanced growth at re-entrant corners of {110} twinned crystals of polyethylene. The supercooling dependence of nucleation rate is two times as strong as that of growth rate; this fact suggests that the growth is by multi-nucleation (regime II). The velocity of steps is proportional to the concentration of solution and nucleation rate is independent of the concentration over the usual concentration range. These relations suggest that the growth face is saturated with adsorbed polymer molecules and the travelling of steps is controlled by the volume diffusion of polymer in the solution. The method described can be applied to other systems which have the same type of re-entrant corner.
    Download PDF (768K)
  • Izumi Iwasa
    1987 Volume 56 Issue 5 Pages 1635-1637
    Published: May 15, 1987
    Released on J-STAGE: May 29, 2007
    JOURNAL RESTRICTED ACCESS
    The vacancy formation energy φ and the vacancy formation entropy s in bcc 3He crystals at high molar volumes VM between 24.356 and 24.922 cm3/mole are determined from the pressure measured as a function of temperature. The highest value of VM is very close to the maximum molar volume of bcc 3He, Vc=24.94 cm3/mole. The value of φ decreases between 4.84 K and 2.17 K with increasing VM. The present results do not agree with a speculation from the NMR results that φ vanishes at Vc. The value of s changes from −1.07 k to −4.32 k with increasing VM. The origin of the negative entropy of formation is probably the ferromagnetic polarization of nuclear spins around a vacancy.
    Download PDF (324K)
  • Jun Kondo
    1987 Volume 56 Issue 5 Pages 1638-1641
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    The renormalization constant for the tunneling matrix of a heavy particle in metals has been investigated theoretically. When the renormalization constant is written as (kTD)K, the cut-off D turns out to be of the order of N0, where ω0 is the frequency of the particle motion in each well and NkFa (a: the distance between the two wells; kF: the Fermi wave number).
    Download PDF (380K)
  • Masao Arai, Tetsuji Tokihiro, Takeo Fujiwara
    1987 Volume 56 Issue 5 Pages 1642-1644
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    We investigate the effect of a uniform magnetic field on the electronic states of the two-dimensional Penrose lattice with the use of periodic Penrose lattices. All states contribute to form the first Landau band in an appropriately strong magnetic field, but the states in the higher energy region do not form the higher Landau levels.
    Download PDF (344K)
  • Yoh Kohori, Takao Kohara, Yoshio Kitaoka, Kunisuke Asayama, M. B. Mapl ...
    1987 Volume 56 Issue 5 Pages 1645-1648
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    The nuclear spin lattice relaxation rates, 1⁄T1, of 55Mn and 59Co have been measured in U6Mn and U6Co, respectively. In both cases, the behavior of 1⁄T1 is consistent with a BCS superconductor in the exchange-enhanced Fermi liquid state.
    Download PDF (388K)
  • Toshirou Yagi, Hiroshi Fujisaki, Akira Sakai
    1987 Volume 56 Issue 5 Pages 1649-1652
    Published: May 15, 1987
    Released on J-STAGE: May 29, 2007
    JOURNAL RESTRICTED ACCESS
    The temperature dependence of the spontaneous polarization PS(T) of the deuterated dicalcium strontium propionate (DDSP) has been observed in a temperature range from room temperature to 240 K by the Sawyer-Towar method under a 60 Hz a.c. field. Near the ferroelectric transition point TCD, PS(T) is well-described by the relation PS(T)∼(TCDT)0.42. The nondeuterated compound (DSP) also shows a similar dependence on temperature PS(T)∼(TCHT)0.40, where TCH is the transition temperature of DSP. The distinct effect of deuteration is found on the magnitude of PS; the ratio of PS of DDSP to that of DSP is about 0.7 at every temperature in the range considered here. A structural isotope effect is suggested to take place in the deuterated propionic molecules and/or in the network formed by metallic cations.
    Download PDF (468K)
  • Masaharu Tokunaga
    1987 Volume 56 Issue 5 Pages 1653-1656
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    By the use of the analogy between the self-consistent phonon theory and the self-consistent renormalized spin fluctuation theory on itinerant electron ferromagnets, the Curie-Weiss susceptibility in displacive-type ferroelectrics is shown to consist of two different mechanisms, (a) the decrease in the mean square amplitude of the soft mode and (b) the increase in the correlation between dipoles. The ratio of the paraelectric moment to the saturated moment is calculated from experimental data in typical ferroelectrics. The great deviation of this ratio from unity in displacive-type ferroelectrics is shown to be attributed to the mechanism (a), and the appearance of the relaxation mode in dynamical spectra to (b).
    Download PDF (464K)
  • Yoshihiro Ohmura, Sh\={u}ichi Sat\={o}
    1987 Volume 56 Issue 5 Pages 1657-1660
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    The inelastic scattering of γ-rays by a bound electron is investigated theoretically for the case of ka∼1, where hk is the momentum transfer of the primary γ-ray and a is the orbital radius of the bound electron, respectively. By the use of orthogonalized plane wave (OPW) for an electron wave function in the scattering state, the result of calculation is compared with that of the experiment obtained by Namikawa and Hosoya (Phys. Rev. Lett. 53 (1984) 1606): scattering of 59.57 keV γ-rays by K-shell electrons of Cu. The C peak and R peak in the experimental spectrum are obtained theoretically, but the height of the R peak is approximately 1/3 that of the experimental result.
    Download PDF (420K)
  • Masaho Tsukada
    1987 Volume 56 Issue 5 Pages 1661-1663
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    A pair of functions −ζ±(x, x′)=−[|xx′|±(xx′)]⁄2 are considered as Green’s functions for one-dimensional Laplace operator by giving some examples. It is shown that these functions can be understood to be generalized functions by the Fourier transform of the differential equation ∇2G(x)=−δ(x).
    Download PDF (300K)
  • Noriko Saitoh, Satoru Saito
    1987 Volume 56 Issue 5 Pages 1664-1674
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    Hirota’s bilinear difference equation (discrete analogue of two dimensional Toda lattice) is formulated in a gauge symmetric form. A linear Bäcklund transformation is derived from the duality of gauge fields and field amplitudes and is solved explicitly. Some properties of the solutions and a relation to scattering amplitudes of the inverse scattering method are discussed.
    Download PDF (1240K)
  • W. Malfliet, J. Bruyndonckx
    1987 Volume 56 Issue 5 Pages 1675-1683
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    Starting from the initial condition
    (Remark: Graphics omitted.)
    we study numerically and analytically the interaction of a KdV soliton with the dispersive wave train. We derive dynamical equations for the soliton part as well as for the non-soliton contribution. These equations can be further reduced to a set of interacting KdV equations. Numerical computations are performed to describe the mutual interaction.
    Download PDF (740K)
  • Takasi Endo
    1987 Volume 56 Issue 5 Pages 1684-1692
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    There are two kinds of dephasing (phase relaxation): statistical phase relaxation (SPR) and quantum-mechanical phase relaxation (QPR). SPR comes from statistical ensemble averaging. QPR comes from the trace over an environmental system. SPR represents a dynamic process of an ensemble but QPR represents one of an individual member of the ensemble. This classification makes the meaning of dephasing clear. A spectroscopic interpretation of dephasing is described.
    Download PDF (1048K)
  • Tomoko Ohyama-Yamaguchi
    1987 Volume 56 Issue 5 Pages 1693-1702
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    Total double- and single-charge transfer cross sections are calculated for the collisions of C6+ ion with He atom in the impact energy region 0.1≤E≤10 keV/amu. The perturbed-stationary-state method in the impact parameter approximation is used with a basis set of SCF–CI molecular orbitals. There are many curve crossings among the adiabatic potential curves. A diabatic treatment is, however, found to be useful for the most of curve crossings. The single-charge transfer mainly occurs through the avoided crossing near 5 au, while the double-charge transfer takes place via a two-step one-electron transfer or a direct process. Hence the double-charge transfer cross section obtained(∼10−16 cm2) is about a tenth of the single-charge transfer cross section in these impact energies.
    Download PDF (1120K)
  • Masakatsu Higa, Tsuguo Takahashi
    1987 Volume 56 Issue 5 Pages 1703-1712
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    The flow induced by an oscillating sphere in a viscous fluid otherwise at rest is analyzed theoretically. The sphere oscillate asymmetrically in translational direction with small amplitude. The steady secondary flow which occurs outside the boundary layer around the sphere is studied by using the method of matched asymptotic expansion. It is found that the asymmetrical steady flow, which vanishes at infinity, is induced near the sphere. The steady drag exerted on the sphere also obtained.
    Download PDF (852K)
  • Nabil T. Eldabe
    1987 Volume 56 Issue 5 Pages 1713-1716
    Published: May 15, 1987
    Released on J-STAGE: May 29, 2007
    JOURNAL RESTRICTED ACCESS
    This paper examines further the flow structure at a rear stagnation point of an incompressible viscous porous medium fluid in the presence of a uniform magnetic field. The effect of the interaction parameter and permeability parameter on the skinfriction have been studied analytically and numerically.
    Download PDF (352K)
  • Nobumasa Sugimoto, Noriyuki Nakajima, Tsunehiko Kakutani
    1987 Volume 56 Issue 5 Pages 1717-1730
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    This paper develops an ‘edge-layer’ theory for weakly nonlinear shallow-water waves propagating over a step bottom. Introducing an ‘edge-layer’ in the vicinity of the step, the matched-asymptotic expansion method is applied to establish ‘reduced’ boundary conditions relevant to Boussinesq equations in the uniform shallow-water regions extending on the outside of the ‘edge-layer’. From the matching conditions, two ‘reduced’ boundary conditions are derived which incorporate the higher-order corrections to the well-known Lamb’s conditions. On applying the conditions thus derived, a problem of reflection and transmission of a single soliton incident upon the step is discussed. It is found that for a moderate depth-ratio, Lamb’s conditions still provide correct boundary-values except the phase shift at the step.
    Download PDF (1540K)
  • Hiromichi Ezumi, Masahiko Kawamura
    1987 Volume 56 Issue 5 Pages 1731-1737
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    The slope constants of the excitational cross-section for atom-atom and atom-electron collisions were generally considered and that for the oxygen atom-atom collision S0–0 was determined to be 3.14×10−19 cm2/eV. Using the newly determined value of S0–0, the calculation of the ionizing shock structure of argon-oxygen mixture was made at shock Mach number Ms=17.1 and the initial pressure P1=2.85 Torr. From the comparison of the calculated value of relaxation length with the experimental one, it was proved that the experimental result can be explained well by the present deter-mined value of S0–0.
    Download PDF (668K)
  • Noriyoshi Nakajima
    1987 Volume 56 Issue 5 Pages 1738-1749
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    In an RFP plasma with relatively high Lundquist number S, nonlinear phenomena due to a single non-resonant current-driven mode with poloidal mode number m=1 are examined by using a numerical simulation of an incompressible plasma. In contrast to the low S number case, a new phenomenon, i.e., a nonlinear oscillation is observed, which is brought about by the nonlinear interaction of the m=1 mode with itself. This nonlinear oscillation occurs around a helical equilibrium in close vicinity to the initial axisymmetric equilibrium and is damped by the energy cascade to the higher harmonics and dissipation. The higher harmonics convert the global flow pattern into the local one, which creates anti-parallel magnetic field lines. Consequently, a nonlinear reconnection occurs after the nonlinear oscillation is completely or almost completely damped.
    Download PDF (1464K)
  • Katsumichi Hoshino, Takumi Yamamoto, Hisato Kawashima, Toshihiko Yamau ...
    1987 Volume 56 Issue 5 Pages 1750-1764
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    Time evolution and profile of peripheral electron temperature during the H-mode like transition in a tokamak plasma is measured using the second and third harmonic of electron cyclotron emission (ECE). The so called “H-mode” state which has good particle/energy confinement is characterized by sudden decrease in the spectral line intensity of deuterium molecule. Such a sudden decrease in the line intensity of Dα with good energy confinement is found not only in divertor discharges, but also in limiter dischargs in JFT-2M tokamak. It is found by the measurement of ECE that the peripheral electron temperature suddenly increases in both of such phases. The relalion between H-transition and the peripheral electron temperature or its profile is investigated.
    Download PDF (1972K)
  • Masatoshi Wakagi, Mitsuo Chigasaki, Masaharu Nomura
    1987 Volume 56 Issue 5 Pages 1765-1772
    Published: May 15, 1987
    Released on J-STAGE: May 29, 2007
    JOURNAL RESTRICTED ACCESS
    Extended X-ray absorption fine structure measurements were made on amorphous germanium, a-Ge, and hydrogenated amorphous germanium, a-Ge:H, both prepared at the substrate temperature of 50°C by sputtering. The first nearest neighbor distances of a-Ge and a-Ge:H are longer than that of crystalline germanium, c-Ge, by 0.016 Å and 0.011 Å, respectively. The Debye-Waller factor, Δσ, and the third moment of the first nearest neighbor distribution, ⟨Δr3⟩, were also determined. The relationships among the first nearest neighbor distance, Δσ and ⟨Δr3⟩ are in agreement with theoretical results derived from thermodynamics. These results suggest the existence of states corresponding to several hundred degrees quenched in a-Ge and a-Ge:H. Furthermore, the state of a-Ge is estimated to be about one hundred degrees higher than that of a-Ge:H.
    Download PDF (868K)
  • Haruyuki Takahashi, Shigeru Tamaki, Shoichi Sato
    1987 Volume 56 Issue 5 Pages 1773-1778
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    The electron density distribution in β-AgI was investigated on the basis of X-ray intensity data obtained by single crystal diffractometry. Several broad peaks observed on the difference Fourier map indicate that β-AgI is not a highly ionic-bonded compound. The charge accumulation on Ag–I bond along the c-axis explains the existence of a low-lying TO mode and the fact that β-AgI is easily cleaved parallel to the hexagonal plane like a layered compound. Present result in the charge distribution suggests an importance of the d-s hybridization in hexagonal AgI as well as linear coordinated silver compounds.
    Download PDF (704K)
  • Eiji Kato
    1987 Volume 56 Issue 5 Pages 1779-1784
    Published: May 15, 1987
    Released on J-STAGE: May 29, 2007
    JOURNAL RESTRICTED ACCESS
    The hypersonic sound velocities in Polystyrene (quinoline) and polystyrene (pyridine) gets, quinoline and pyridine liquids and the cross-linked polystyrene polymer are measured using the technique of Brillouin scattering as a function of temperature. Comparing these results with the theory of Marqusee and Deutch, we find the sound velocities in the present gels excellently agree with the theoretical ones considering the strong coupling (λ=1) between the elastic waves in the polystyrene network and the solvent quinoline or pyridine. The values of the estimated elastic constant of longitudinal waves of the swollen polystyrene network are in the order of 108 N·m−2, which nearly equal to the values of gum-like polymers in the high frequency region.
    Download PDF (572K)
  • Kiyosi Motida
    1987 Volume 56 Issue 5 Pages 1785-1793
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    A lattice dynamical model including covalency effects for the alkali halides (J. Phys. Soc. Jpn. 55 (1986) 1636) is extended so as to contain the mechanism of the short-range-force- induced charge flow. It is shown that this mechanism does not improve significantly the agreement between the calculated and observed dispersion curves, but gives a reasonable explanation for the sign reversal of the elastic constant C44C12 observed among the alkali halides.
    Download PDF (1032K)
  • Shun-ichiro Koh, Yasusada Yamada
    1987 Volume 56 Issue 5 Pages 1794-1809
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    A model of reconstruction process of discommensuration lattice (DL) after a sudden change of temperature within IC-phase of quartz is proposed. The triangular pattern observed by electron microscopy in the IC-phase of quartz is interpreted in terms of discommensurations associated with B1 phonon mode propagating along the three equivalent directions within hexagonal basal plane. In analogy to dislocations in the crystal growth, a particular type of defect in hexagonal DL are thought to play an important role in the reconstruction process. The process is composed of (i) nucleation of DL defect, (ii) jump diffusion of defects in the asymmetric directions, (iii) relaxation of discommensuration lines, (iv) pair annihilation of DL defects. Recent in-situ observation of heating process of quartz seems to confirm partly the proposed model.
    Download PDF (2196K)
  • Kazuko T. Mashiyama, Hiroyuki Mashiyama
    1987 Volume 56 Issue 5 Pages 1810-1814
    Published: May 15, 1987
    Released on J-STAGE: May 29, 2007
    JOURNAL RESTRICTED ACCESS
    Structures of domain walls in the commensurate phase and an order of the incommensurate-commensurate transition in proper ferroelectrics are investigated on the basis of the phenomenological free energy with an elastic term. Apart from the oscillatory domain wall previously found, the domain wall with an exponential decay is shown to exist. The asymptotic interaction between discommensurations is calculated theoretically, and is shown to be attractive, irrespective of the different behaviours of the domain wall. The transition is first-order one, in agreement with the numerical calculation. This differs from the case of improper ferroelectrics, whose transition can be either continuous or discontinuous even when the tail of the domain wall decays monotonically.
    Download PDF (648K)
  • Akira Mishima, Hiroshi Miyagi
    1987 Volume 56 Issue 5 Pages 1815-1827
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    The high temperature expansion for the free energy is evaluated up to the seventh moment, for hcp phase of solid ortho-para mixtures. It is proved that the resultant high-temperature series is divergent far above the transition temperature Tc. The Padé approximation to the high-temperature series for the entropy is studied in excellent agreement with experiments down to Tc. For pure ortho hydrogen, Tc is predicted to be 2 ΓkB lower than the experimental one. The phase transition disappears at concentration ∼63% of ortho hydrogen in agreement with experiment. In these studies a previous result based on the libron study of ortho-para mixtures is utilized, for the free energy in the low temperature phase of fcc.
    Download PDF (1448K)
  • Koji Honma, Keiichi Iida
    1987 Volume 56 Issue 5 Pages 1828-1836
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    Specific heat capacities of “superionic conductor”, Ag chalcogenides have been measured for Ag2S, Ag2Se and Ag2Te in the temperature range, 120–520 K. In every case, the heat capacity at constant pressure, Cp, decreases with increasing temperature over the fairly wide range above transition temperature. The behavior of the excess specific heat capacity can be explained fairly well as the transition of Ag+ ions between two or more types of sites in the average structure, by a quasi-chemical method, applied to the theory of order-disorder transformations.
    Download PDF (1064K)
  • Takeshi Hiraoka, Kaoru Kamihira
    1987 Volume 56 Issue 5 Pages 1837-1840
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    Electrical resistivity in NdIn3 has been measured from 4.2 to 300 K. The role of exchange and quadrupolar scatterings under the effect of CEF is studied and the latter scattering is shown as important as the former one. Taking into account the effect of the quadrupolar scattering, the observed resistivity is well fitted with the CEF ground state of Γ8(1) with the parameters as reported previously.
    Download PDF (416K)
  • Kunihiko Yamaji
    1987 Volume 56 Issue 5 Pages 1841-1854
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    The dependence of the subtitle is studied on the magnetic-field-induced SDW (FI–SDW) and the transient type of SDW (SDW2) in the boundary region around the parameter region of the stable SDW on the basis of numerical computation of the ground state energy and consideration on the electronic structure. Reversal of the current carrier type on appearance of the Fl–SDW and SDW2 is clarified with realistic values of the parameter set. The amount of energy gain due to the orbital quantization in the field is improved. Although the field-dependence of magnetization is not so improved, the average period of transitions among the Fl–SDW subphases is found in the accessible range of reasonable models. There appear new features of the phase diagram such as jump of the magnetic quantum number by more than one and a phase boundary between zones of positive and negative shifts of Qy.
    Download PDF (1856K)
  • Takao Furubayashi, Isao Nakatani, Norio Saegusa
    1987 Volume 56 Issue 5 Pages 1855-1858
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    Magnetization and Mössbauer spectroscopy measurements are reported for fine particles of iron, 20 Å in average diameter, dispersed in oil by a surface-active agent. The magnetic moment per atom was obtained from the saturation magnetization. The value at 4.2 K was 2.28μB, which is larger than that in bulk iron. It was confirmed from the Mössbauer spectroscopy that the particles are free from oxidation. The hyperfine field Hhf at 4.2 K was distributed in the range from 300 kOe to 400 kOe. The average of Hhf was enhanced as compared with the bulk value correspondingly to the increase in the magnetic moment.
    Download PDF (620K)
  • Kazuoki Kuramoto
    1987 Volume 56 Issue 5 Pages 1859-1867
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    Dielectric dispersion relating to the “domain freezing” of KH2PO4 crystals has been observed in the frequency range from 110 Hz to 1 GHz. A clear dispersion of a relaxational type is found in the ferroelectric phase above the piezoelectric resonant frequency. This dispersion can be described with the relaxation time τ which obeys a Vogel-Fulcher law, τ=τ0 exp {E⁄(TT0)}, with a Gaussian distribution of the activation energy, f(E)=(\sqrt2πσ)−1 exp {−(EE0)2⁄2σ2}. When the temperature is lowered, the relaxation times become longer; and crossover of the relaxational dispersion and the piezoelectric resonance arises around 100 K below which the dielectric constant of the free crystal decreases remarkably. It is concluded that the “domain freezing” is caused by the Vogel-Fulcher behavior of the relaxational dispersion.
    Download PDF (924K)
  • Akio Miyazaki, Yasuharu Makita
    1987 Volume 56 Issue 5 Pages 1868-1873
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    The dielectric constant of NaNH4SO4·2H2O at 10 kHz and 9.4 GHz, and its elastic stiffnesses at constant electric field (1⁄s66E) and at constant electric polarization (1⁄s66P) have been measured as functions of temperature above the Curie temperature (Tc). It is observed that both the dielectric constant of a clamped crystal ε33c and the elastic compliance s66P follow the Curie-Weiss law, as in the cases of the dielectric constant of a stress-free crystal ε33f and the elastic compliance s66E. It is found that the extrapolated Curie temperature T0 is −300 K for s66P and 6 K for ε33c. The experimental results are discussed shortly on the basis of the Landau theory.
    Download PDF (588K)
  • Kazuyuki Mito, Masamitsu Hirai
    1987 Volume 56 Issue 5 Pages 1874-1880
    Published: May 15, 1987
    Released on J-STAGE: May 29, 2007
    JOURNAL RESTRICTED ACCESS
    F center formation connected with S−− ions in KCl single crystals has been investigated under UV (4.9 eV) light illumination. Following results are obtained. (1) Luminescence bands at 3.16 eV and 2.57 eV due to S−− ions are observed at low temperatures, but the former luminescence quenches with an activation energy of ∼260 meV above ∼180 K. (2) The F center and a center called X center are produced by UV illumination above ∼200 K instead of the luminescence, but there is no complete complemental correlation between temperature dependence of the luminescence quenching and of the X and F center formation. (3) The X center may be an F center perturbed by the nearest S ion, i.e. [S+F] in a ⟨110⟩ direction, and exhibits three absorption bands at 1.9 eV, 2.1 eV and 2.3 eV. (4) The X centers are converted thermally to the F centers, possibly by dissociation of [S+F] with an activation energy of ∼550 meV above ∼250 K. Conversion mechanism is discussed.
    Download PDF (704K)
  • Hiro-o Yugami, Shin-ichi Nakashima, Katsuya Sakai, Haruo Kojima, Masan ...
    1987 Volume 56 Issue 5 Pages 1881-1889
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    Raman scattering spectra from plasmon-LO-phonon coupled modes in n-ZnSe crystals have been measured. Upper- and lower-branches of the coupled modes have been observed clearly in polarized Raman spectra. It is found that the scattering intensity of the coupled modes depends on the magnitude of the momentum transfer of electrons. This result indicates that the charge density fluctuation mechanism as well as the deformation potential and electro-optic mechanisms contribute to the Raman scattering from the coupled modes in ZnSe. Calculated line-shapes reproduce the observed spectra well. From the line-shape fitting, carrier concentration and plasmon damping constant are determined.
    Download PDF (996K)
  • Eiji Yamaichi, Koichi Watanabe, Koji Imamiya, Kikuo Ohi
    1987 Volume 56 Issue 5 Pages 1890-1897
    Published: May 15, 1987
    Released on J-STAGE: May 29, 2007
    JOURNAL RESTRICTED ACCESS
    The photoluminescence was observed in undoped KTaO3 single crystal under the illumination of the band-gap light at low temperatures. The emission spectrum at 49 K shows an asymmetric broad band peaked at 2.6 eV. It can fit in with superimposed two Gaussian curves peaked at 2.61 eV and 2.28 eV. As the temperature increases, the intensity of the 2.61 eV emission band decreases steeply. The emission spectrum at 83 K can be fit in with one Gaussian curve peaked at 2.1 eV. The decay of the photoluminescence was measured using a N2 pulse laser. The decay kinetics of the 2.61 eV emission band can be explained by the theory of the recombination of electrons trapped on donors and holes trapped on acceptors. The temperature dependence of the luminescence can be explained by thermal ionization of holes on acceptors in parallel with the donor-acceptor recombination.
    Download PDF (764K)
  • Tomoyuki Nagaya, Hiroshi Orihara, Yoshihiro Ishibashi
    1987 Volume 56 Issue 5 Pages 1898-1904
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    The equation of motion of disclinations in the non-orthogonally twisted nematic cell is derived. The experimental results on a liquid crystal MBBA are presented and discussed.
    Download PDF (592K)
  • Kohei Furuno, Tetsuro Komatsubara, Takeshi Hosoda, Hideo Sakamoto, Tak ...
    1987 Volume 56 Issue 5 Pages 1905-1906
    Published: May 15, 1987
    Released on J-STAGE: May 29, 2007
    JOURNAL RESTRICTED ACCESS
    Download PDF (252K)
  • Tadashi Kambara, Yohko Awaya, Masayuki Kase, Hidekazu Kumagai, Hiromi ...
    1987 Volume 56 Issue 5 Pages 1907-1908
    Published: May 15, 1987
    Released on J-STAGE: May 29, 2007
    JOURNAL RESTRICTED ACCESS
    Download PDF (220K)
  • Hideaki Monji, Makoto Onizawa
    1987 Volume 56 Issue 5 Pages 1909-1910
    Published: May 15, 1987
    Released on J-STAGE: May 29, 2007
    JOURNAL RESTRICTED ACCESS
    Download PDF (364K)
  • Hiroshi Kohno, Toshihiko Tsuneto
    1987 Volume 56 Issue 5 Pages 1911-1912
    Published: May 15, 1987
    Released on J-STAGE: June 01, 2007
    JOURNAL RESTRICTED ACCESS
    Download PDF (160K)
feedback
Top