-
Kiyoshi Sogo
Subject area: Mathematical methods in physics.
1995 Volume 64 Issue 7 Pages
2249-2251
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
Creation and annihilation operators of anyons are constructed explicitly by using vertex operators for the Calogero-Sutherland-Moser model.
View full abstract
-
Masato Hisakado, Miki Wadati
Subject area: Mathematical methods in physics.
1995 Volume 64 Issue 7 Pages
2252-2256
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
Motion of discrete surfaces (triangulate surfaces) in 3-dimensional space is discussed. A set of formulae, corresponding to to the Gauss-Weingarten equation and the Gauss-Codazzi equations, is presented to represent the discrete surface. The kinematical relation for the velocity yields a differential-difference equation for the “ normal curvature''.
View full abstract
-
Kazuhiro Hikami
Subject area: Mathematical methods in physics.
1995 Volume 64 Issue 7 Pages
2257-2260
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
The Dunkl operator is constructed based on the Yang-Baxter equation.We regard the R- and K-matrix, which satisfy the Yang-Baxter equation and th boundary Yang-Baxter equation, as operators acting on the functional space.In terms of these R- and K-operators acting on the functional space.In terms of these R- and K-operators, the Dunkl operator with boundary is explicitly construction.
View full abstract
-
Jian–Zhong Ma, Hiroshi Hasegawa
Subject area: Statistical physics and thermodynamics.
1995 Volume 64 Issue 7 Pages
2261-2265
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
Using Gaudin's model (Nucl. Phys. 85 (1966) 545), we study the asymptotic behavior of the number variance of quantum levels whose statistics is subject to a one-parameter family of the predicted distributions which lie in the Poisson and the circular unitary ensembles. It is shown that the variance function ∑
2(S) for S>> 1 is a sum of a linear term and a logarithmic term, originating from the Poisson and the GUE (Gaussian unitary ensemble) results, respectively. The linearity of the leading term is attributed to Gaudin's treatment of the system as a compressible gas, thus verifying the prediction in a recent paper by Moshe, Neuberger and Shapiro (Phys. Rev. Lett. 73 (1994) 1497). A possibility of alternative treatment for incompressible gases is discussed.
View full abstract
-
Norio Inui
Subject area: Statistical physics and thermodynamics.
1995 Volume 64 Issue 7 Pages
2266-2269
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
We study an interacting particle system with parity conservation for the number of particles, which exhibitits a continuous phase transition. Using Padé approximants for the survival probability, we obtain critical probability p
c=0.3585± 0.0021 and critical exponent β =0.97± 0.08. The results show that the model belongs to a universality class different from that of directed percolation.
View full abstract
-
Setsuo Ichimaru, Hikaru Kitamura
Subject area: Nuclear reactions and scattering: general.
1995 Volume 64 Issue 7 Pages
2270-2273
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
By combining the concepts of pycnonuclear reactions at low temperatures and their enhancement due to strong internuclear Coulomb correlations, we predict the possibilities of a novel scheme for fusion in ultrahigh-pressure liquid-metallic hydrogen near the freezing conditions, for the reactions
2H(p, , γ )
3He,
3H(d, , n)
4He, and
7Li(p, , α )
4He. Time evolution is followed for p-d reaction after a pulsed compression with 1, kJ input and the initial conditions of mass density≈ 20, g/cm
3, temperature≈ 1400, K, pressure≈ 490, Mbar, and radius≈ 0.017, cm; an energy yield of 33, kJ in 0.03, fs is thus predicted.
View full abstract
-
Hiroyuki Honji, Yukikado Haraguchi
Subject area: Fluid dynamics.
1995 Volume 64 Issue 7 Pages
2274-2277
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
Quasi-two-dimensional vortex pairs induced by the Lorentz force due to an electrolytic current interacting with a moving magnetic field were investigated using a flow visualization technique. Steady symmetric vortex pairs were found to form in a limited range of Reynolds number and reduced Lorentz force. It was also found that at large values of the force periodic vortical wakes are formed with the Strouhal number of about 0.1.
View full abstract
-
P. K. Shukla, Yoshiharu Nakamura, Mitsuhiro Nambu, S.V. Vladimiriv
Subject area: The physics of plasmas and electric discharges.
1995 Volume 64 Issue 7 Pages
2278-2281
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
The nonlinear coupling between fast and slow dust-acoustic waves in dusty plasmas hasbeen considered.The multi-fluid equations have been used to derive a set of equations whichis useful for studying the three-wave decay interaction as well as the modulational instabilityof the fast dust-acoustic waves
View full abstract
-
Tohru Ozaki, Kentarou Fujii, Junji Ohgami
Subject area: Structure of liquids and solids; crystallography.
1995 Volume 64 Issue 7 Pages
2282-2285
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
Ferroelectric 180° domain structures of CsH
2PO
4 (CDP) and (NH
2CH
2COOH)
3· H
2SO
4 (TGS) have been observed in unelectroded b plates using the secondary emission mode of a scanning electron microscope (SEM). It is found that a lamellar domain structure is formed in CDP. The lamellar structure shows the fine periodicity along the normal to the walls nearly parallel either to the (100) plane or to the (801) plane. The periodic pattern corresponds to the first prefractal domain pattern that is characterized by the first prefractal of the pentad Cantor set. It is also revealed that the lamellar domain structure of TGS is observed to be the first prefractal domain pattern. The SEM observations establish that the prefractal domain patterns first dis-covered in KDP are common to the lamellar 180° domain structures which areformed in proper ferroelectrics under the influence of depolarization fields.CDP, TGS, ferroelectric domain, SEM, fractal, Cantor set, depolarization field, surface energy density
View full abstract
-
Rinna Kanao, Shin–ichiro Nohdo, Noriaki Horiuchi, Shoji Kashida, ...
Subject area: Equations of state, phase equilibria, and phase transitions.
1995 Volume 64 Issue 7 Pages
2286-2289
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
The phase transition mechanism of KDCO
3 crystal composed of hydrogen-bonded (DCO
3)
2-dimers has been studied by neutron scattering. Strong quasielastic diffuse scattering is observed above T
c. From detailed analysis of the intensity distribution in a wide range of the reciprocal space, the following conclusions are drawn. (i) Even at T>T
c, the individual dimer is already deformed by the self-trapping of deuterons within the hydrogen bond, thus locally breaking the symmetry of the averaged lattice. (ii) The inter-dimer interaction takes place via the strain field induced by the independent deformed dimers. The structural phase transition in KDCO
3 is triggered by this strain-mediated indirect interaction between the dimers.
View full abstract
-
Osamu Narikiyo, Kazumasa Miyake
Subject area: Electron states in condensed matter.
1995 Volume 64 Issue 7 Pages
2290-2293
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
The one-particle spectral weight of the two-dimensional Hubbard model is studied in the t-matrix approximation. A single quasi-particle peak is obtained in the spectrum so that the quasi-particle picture holds in the t-matrix approximation, while in the second-order perturbation (H. Fukuyama and M. Ogata: J. Phys. Soc. Jpn. 63 (1994) 3923) it is concluded that splitting of the spectral weight occurs.
View full abstract
-
Tadao Kasuya
Subject area: Electron states in condensed matter.
1995 Volume 64 Issue 7 Pages
2294-2297
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
Anomalous properties in U and Np monopnictides are explained based on the orbit split Hartree-Fock-type 5f band model. In particular, the de Haas-van Alphen measurement in USb in the 3k magnetic order is explained very well in the present model accompanied by a strong electron-hole nesting, which is consistent with a strong increase in resistivity and very small electronic specific heat in the 3k ordering region.
View full abstract
-
Yoshikazu Suzumura, Noriko Tanemura
Subject area: Electron states in condensed matter.
1995 Volume 64 Issue 7 Pages
2298-2301
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
Fluctuations of both charge density and spin density around the mean-fields of the spin density wave (SDW) state have been studied by calculating collective modes inthe case of one-dimensional quarter-filled band and arbitrary magnitude of the inter-action. It is shown that the coexistence of the 2k
F-SDW with the 4k
F-charge densitywave is crucial for the commensurability energy and the collective mode of the density fluctuation.
View full abstract
-
Shinya Tokizaki, Yoshio Kuramoto
Subject area: Electron states in condensed matter.
1995 Volume 64 Issue 7 Pages
2302-2306
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
The ground state as well as low-lying excitations in a 2D electron system in strong magnetic fields and a parabolic potential is investigated by the variational Monte Carlo method. Trial wave functions analogous to the Laughlin state are used with the power-law exponent as the variational parameter. Finite size scaling of the excitationenergy shows that the correlation function at long distances is characterized by a non-universal exponent in sharp contrast to the standard Laughlin state. The Laughlin-type state becomes unstable depending on the strength of the confining potential.
View full abstract
-
Harukazu Yoshino, Kazuya Saito, Koichi Kikuchi, Hiroyuki Nishikawa, Ke ...
Subject area: Electronic transport in condensed matter.
1995 Volume 64 Issue 7 Pages
2307-2310
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
Angular dependence of magnetoresistance of a quasi-one-dimensional organic superconductor, (DMET)
2I
3 has been measured at 4.2, K for magnetic fields up to 7.0, T. For the field of 1.0, T, the angular dependence of the magnetoresistance is smooth over the entire range of angles, reflecting the quasi-one-dimensional band structure of the salt. When the magnetic field of 7.0, T was rotated in the most conducting ab plane, the magnetoresistance for the current along both the b- and c
*-axes showed discontinuous changes in its slope at the angles of ± 15° from the most conducting axis. The anomaly occurring at 7.0, T is considered to be due to a change in electronic state induced by the magnetic field almost perpendicular to the quasi-1D Fermi surface.
View full abstract
-
Tohru Okamoto, Yoshinori shinohara, Shinji Kawaji, Atsuo Yagi
Subject area: Electronic structure and electrical properties of surfaces, interfaces and thin films.
1995 Volume 64 Issue 7 Pages
2311-2315
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
We have experimentally studied metal-insulator transitions in a two-dimensional electron system in Si-MOSFET's in a magnetic field and derived a phase diagram on aν (Landau level filling factor) vs. disorder (resistivity in the absence of magnetic field)plane. Structures of stabilized phase boundaries at ν =1 and ν =2 are discussed based on many-body enhancement of valley- and Zeeman-splitting, respectively.
View full abstract
-
Munehiro Azami, Akito Kobayashi, Tamifusa Matsuura, Yoshihiro Kuroda
Subject area: Superconductivity.
1995 Volume 64 Issue 7 Pages
2316-2320
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
Charge-fluctuation-mediated superconductivity in the simplest d-p model is investigated using the auxiliary boson method together with the 1/N-expansion theory. The transition temperature T
c is determined by solving the Eliashberg equation derived for the pairing interaction including the full momentum and frequency dependence. The pairing state with the highest T
c has an extended s-symmetry described mainly by the on-site and the nearest-neighbor pairings. While the pairing interaction is repulsive over almost the entire momentum space, the frequency dependence, i.e., the retardation effect, is essential to realize such a superconducting state. The order of magnitude of T
c is estimated to be \le230, K with a reasonable set of the parameters, which means that the charge fluctuation plays a crucial role in the system.
View full abstract
-
Toshifumi Itakura, Norio Kawakami
Subject area: Magnetic properties and materials.
1995 Volume 64 Issue 7 Pages
2321-2324
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
We study critical properties of the one-dimensional integrable Heisenberg model and supersymmetric t-J model with two-band structure. We apply conformal field theory analysis to the Bethe-ansatz solution of these models, and compute bulk susceptibilities and critical exponents. The universal formulas obtained for critical exponents can be applied to nonintegrable spin and electron models with two-band structure.
View full abstract
-
Setsuo Mitsuda, Satoru Kobayashi, Kouji Aga, Hajime Katagiri, Hideki Y ...
Subject area: Magnetic properties and materials.
1995 Volume 64 Issue 7 Pages
2325-2328
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
We report neutron scattering as well as ac susceptibility studies on the formation of magnetic ordering in a quasi-1D ferromagnetic chain system CoNb
2O
6 in magnetic fields up to 600, Oe. At T=1.5, K, a noncollinear ferrimagnetic (FR) phase with up-up-down spin arrangement along the b axis is field-induced in the magnetic field above -- 300, Oe. Interestingly, the pronounced 2D magnetic character previously found in the noncollinear antiferromagnetic phase disappears in the FR phase. This is direct evidence that the 2D magnetic character is due to the cancellation of interchain exchange fields at an apex site of a 2D isosceles-triangular lattice where quasi-1D ferromagnetic chains lie.
View full abstract
-
Keizo Endo, Hiroko Matsuda, Kiyoshi Ooiwa, Kazuo Itoh
Subject area: Magnetic properties and materials.
1995 Volume 64 Issue 7 Pages
2329-2332
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
Antiferromagnetism has been found in a Heusler alloy Fe2VSi from measurements of electrical resistivity, magnetic susceptibility and Mössbauer spectroscopy of 57Fe. The Néel and Weiss temperatures are 123, K and -212, K, respectively. The magnetic moment of an Fe atom estimated from Mössbauer spectrum splitting is 0.22, μ
B at 15, K. The effective moment determined from Curie-Weiss susceptibility above 123, K is 1.87, μ
B. The results are discussed in relation to a half-metallic antiferromagnet.
View full abstract
-
Masahisa Ito, Fumitake Itoh, Yoshikazu Tanaka, Akihisa Koizumi, Hirosh ...
Subject area: Magnetic properties and materials.
1995 Volume 64 Issue 7 Pages
2333-2337
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
A measurement of the magnetic form factor of a ferromagnetic actinide compound of UTe with circularly polarized X-rays is reported. The present geometrical configuration of the measurement gives a form factor of L(k)+0.3S(k), where L(k) andS(k) are the form factors of the orbital and the spin magnetic moment, respectively.We have combined the X-ray magnetic form factor with the neutron one which gives L(k)+2S(k) (G. Busch et, al.: J. Phys. C 12 (1979) 1391), and have deduced L(k) and S(k) separately. The obtained profiles of L(k) and S(k) show that the orbital and the spin magnetic moments are spatially spread out more than those calculated for a free uranium ion.
View full abstract
-
Takayuki Shirakura, Fumitaka Matsubara
Subject area: Magnetic properties and materials.
1995 Volume 64 Issue 7 Pages
2338-2342
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
We study a site-random Ising (SRI) model in two dimensions (2D) using a Monte Carlo method. It is found that the Binder parameter g
L's for different sizes of the lattice L come together at almost the same temperature as in the ± J model in 3D. Finite-size scaling analyses give results which are compatible with the assumption of a finite, nonzero transition temperature (T
c≠ 0), although the scaling temperature range is not large. We suggest that in the SRI model a spin glass (SG) phase transition occurs at T
c≠ 0 even in 2D.
View full abstract
-
Kazuyoshi Takeda, Toshiyuki Hamano, Tatuya Kawae, Masako Hidaka, Minor ...
Subject area: Magnetic properties and materials.
1995 Volume 64 Issue 7 Pages
2343-2346
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
One-dimensional quantum statistics has been studied at the limit of isotropic exchange interaction in the unpaired electron system of a ferromagnetic organic radical crystal, 3-(4-chlorophenyl)-1, 5-diphenyl-6-oxoverdazyl. The characteristic field dependence of the magnetic heat capacity of this crystal is quantitatively explained by the theoretical values derived from the Bethe-ansatz technique applied to the quantum transfer matrix, with a unique intrachain exchange constant J/k
B=5.5, K. By the simultaneous measurement of magnetic susceptibility and heat capacity, the three-dimensional ordering at T
c=0.21, K, which is triggered by a weak interchain coupling | zJ'| /k
B=3× 10
-2, K, is confirmed.
View full abstract
-
Hiroki Yamazaki
Subject area: Magnetic properties and materials.
1995 Volume 64 Issue 7 Pages
2347-2350
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
The magnetic properties of triangular lattice S=3/2 Heisenberg antiferromagnet CsVCl
3 were studied by DC magnetic susceptibility and ESR measurements using reliable pure samples free from Curie-like paramagnetic contributions at low temperatures. At T
N=14.0± 0.2, K, susceptibility exhibited the second-order transition which corresponds to a three-dimensional order with triangular spin arrangement. A spin-freezing phenomenon similar to that of spin glasses was observed below T
f=7.5, K. This behavior suggests that the ground state is not a simple 120° Néel state.
View full abstract
-
Takashi Fujikawa, Tetsuro Yikegaki, Lars Hedin
Subject area: Optical properties and condensedmatter spectroscopy and other interactions of matter with particles and radiation.
1995 Volume 64 Issue 7 Pages
2351-2355
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
We develop an approximation for the optical potential in a solid valid at intermediate energies, i.e., above about 50, eV. The present approximation for the optical potential is based on GW-expression. We separate the RPA polarization propagator into a core-electron and a valence-electron part, and can then achieve a corresponding separation of the optical potential. We apply this method to electron-He elastic scattering, and we find satisfactory agreement with the observed results. We also study the importance of self-consistency, and the sensitivity to a parameter, average excitation energy.
View full abstract
-
Masaru Kai, Arata Tanaka, Takeo Jo
Subject area: Optical properties and condensedmatter spectroscopy and other interactions of matter with particles and radiation.
1995 Volume 64 Issue 7 Pages
2356-2359
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
The difference in 4f photoemission spectrum (PES) for rare earths (RE) Nd, Gd and Dy under off-resonance and various on-resonance conditions near the 3d core threshold is discussed on the basis of an ionic model assuming trivalence. For the resonant process passing through a higher-energy intermediate state of both 3d
5/2 and 3d
3/2 regions, the spectral intensity in higher (lower) binding energy multiplets of 4f PES is shown to be enhanced (suppressed) compared with off-resonance spectra. This tendency is especially remarkable for Gd and heavier rare earths. An intuitive interpretation for this tendency is presented and a control of photoexcitation by tuning photon energy, which may be compared to that using a polarized photon, is shown to be feasible.
View full abstract
-
B. Z. Essimbi, A. M. Dikande, T. C. Kofane, A. A. Zibi
Subject area: Mathematical methods in physics.
1995 Volume 64 Issue 7 Pages
2361-2369
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
A new class of localized solitary signals is investigated on a coupled nonlinear transmission line, which consists of two LC ladder lines connected by intermediary capacitors. Actually, these localized solitary excitations correspond to configurations where electric signal voltages on nearest-neighbour electric cells of each LC ladder line oscillate out of phases with each other, at the same frequency. Thus, it is found that they are stationary nonlinear asymmetric waves, whose amplitudes and widths depend on characteristic parameters of the circuit. The explicit envelope functions which are appropriate for coupled system with finite lengths are also found.
View full abstract
-
Tatyana K. Soboleva, Alexander S. Zeltser, Yuri S. Kivshar, Sergei K. ...
Subject area: Mathematical methods in physics.
1995 Volume 64 Issue 7 Pages
2370-2379
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
We analyze nonlinear waves in layered (anisotropic) structures with strong interlayer interaction. One of the important physical examples of nonlinear modes in such structures is the so-called supersolitons, localized excitations of the density of a vortex lattice propagating in a system of interacting (parallel) long Josephson junctions. We show that the dynamics of these structures may be described by the so-called sine-lattice (SL) equation first introduced by S. Takeno and S. Homma [J. Phys. Soc. Jpn. 55 (1986) 65] and its various generalizations, e.g. those which include a transverse degree of freedom or more general types of the interlayer (nonlinear) interactions described by periodic Jacobi elliptic functions. We analyze nonlinear localized waves in such generalized SL equations analytically and numerically, and show that, in general, density waves may be of three types, namely kinks, dynamical solitons, and envelope solitons. We investigate also the transverse stability of quasi-one-dimensional solitons in the framework of the effective modified Boussinesq equation valid for both small amplitudes and continuous approximation, as well as investigate numerically the effects of perturbations (dissipation or point-like impurities) on the dynamics of π -kinks.
View full abstract
-
Shozo Takeno
Subject area: Mathematical methods in physics.
1995 Volume 64 Issue 7 Pages
2380-2389
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
Dual nature of the existence of localized modes in pure nonlinear lattices is shown as the intrinsic properties of the lattices that cannot be shared with their continuum counterpart. This is a coexistence, for given nonlinearity, of low-and high-frequency localized modes appearing above and below, respectively, of the frequency band of the corresponding linear lattices. As a typical example, this is illustrated for breatherlike mode solutions to sine-lattice equations and discrete sine-Gordon equations using approximate analytical solutions. The duality concept is put into firmer basis by showing the coexistence of such two types of localized modes for exact envelope soliton solutions to the Ablowitz-Ladik equations and for approximate analytical solutions with numerical testing for moving nonlinear localized modes in one-dimensional lattices with hard quartic anharmonicity.
View full abstract
-
Masato Hisakado, Kazuaki Nakayama, Miki Wadati
Subject area: Mathematical methods in physics.
1995 Volume 64 Issue 7 Pages
2390-2393
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
Motion of discrete curves (piecewise linear curves) in the plane is discussed. A discrete analogue of the Frenet-Serret formula is presented. Compatibility of the discrete Frenet-Serret formula and the kinematical relation for the velocity yields a differential-difference equation for the “ curvature''. Relations between the discrete Frenet-Serret formula and the Ablowitz-Ladik scattering problem are shown.
View full abstract
-
Mio Murao, Fumiaki Shibata
Subject area: Statistical physics and thermodynamics.
1995 Volume 64 Issue 7 Pages
2394-2404
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
A new type of the dissipative Jaynes-Cummings model is presented. Interaction between a composite relevant system and a reservoir is introduced to modulate the coupling constant in the relevant system. A quantal master equation is obtained with use of the time convolutionless (TCL) projection operator formalism and is expanded in terms of eigenstates of the composite relevant system. The resulting basic equations become solvable and can be used irrespective of the interaction strength between the relevant subsystems. Moreover, these equations give the correct equilibrium values in each subspace. Several explicit numerical calculations are done.
View full abstract
-
Norio Konno, Kazunori Sato
Subject area: Statistical physics and thermodynamics.
1995 Volume 64 Issue 7 Pages
2405-2412
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
The upper bounds on order parameters of the d-dimensional diffusive contact processes with stirring rate D≥ 0 are obtained by using Harris lemma. Our result generalizes bounds on the d-dimensional basic contact processes---that is, D=0, by Katori and Konno.
View full abstract
-
K. Rajagopal, T. A. Prasadarao
Subject area: Experimentally derived information on atoms and molecules: instrumentation and techniques.
1995 Volume 64 Issue 7 Pages
2413-2419
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
The experimentally determined electro-optic Kerr constant values of some homologous series of organic liquids belonging to Ketone, Aldehyde and Nitriles are combined with the molecular refraction data of these liquids to compute the anisotropic electronic polarizabilities in the ground state. These values are found to be fairly in good agreement with those values reported in literature. The polarizability values are found to be increasing in each homologous series with increasing chain-length by CH
2 intervening groups. This fact has been supported by the predominant nature of the inductive effect that arises due to the structural changes of the molecules in these series.
View full abstract
-
Jiro Mizushima
Subject area: Fluid dynamics.
1995 Volume 64 Issue 7 Pages
2420-2432
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
Thermal instability of a fluid in a finite rectangular box is investigated, assuming the flow field to be two-dimensional. The horizontal plates are assumed to be rigid and perfectly thermal conducting. Three cases of boundary conditions for the vertical side walls are considered, which are rigid and perfectly conducting, rigid and perfectly insulating, and stress free and perfectly insulating boundary conditions. The critical condition of the linear stability of the motionless state is obtained for various aspect ratios of the box. It is concluded that the stability characteristics are very different between the cases of rigid and stress free side walls. Asymptotic expressions of the critical Rayleigh number are obtained for very wide and very narrow boxes respectively. The Moffatt vortices are confirmed up to the second.
View full abstract
-
Shinichiro Yanase, Jiro Mizushima, Keisuke Araki
Subject area: Fluid dynamics.
1995 Volume 64 Issue 7 Pages
2433-2443
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
Finite amplitude steady solutions for convections between two concentric spheres under the effects of differential rotation and temperature difference between the spheres are obtained and their linear stability is investigated numerically. Under the assumption of axisymmetry about the axis of rotation, the solutions are classified into the symmetric solution and the asymmetric solution with respect to the equator. It is found that the symmetric solution consists of the upward solution and the downward solution which have different flow profiles, rates of heat transfer between two spheres. A perfect pitchfork bifurcation is observed for the asymmetric solution, whereas an imperfect pitchfork bifurcation is observed for the symmetric solution, as the rate of the differential rotation is increased.
View full abstract
-
Hiroshi Amemiya
Subject area: The physics of plasmas and electric discharges.
1995 Volume 64 Issue 7 Pages
2444-2454
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
The criterion of sheath formation in a plasma containing negative ions have been investigated for the case with an injected electron beam. It has been found that at a constant negative ion density ratio the sheath edge potential and the positive ion flux increase with the relative electron beam density. From the balance between the flux of negative charged particles and the positive ion flux, the floating potential of a substrate immersed in the plasma is calculated based upon the above sheath theory. It has been found that the floating potential of an insulating substrate is variable with the relative electron beam and negative ion densities in a wide range. This means that in an etching plasma the substrate potential can be controlled by injecting a low density electron shower.
View full abstract
-
A. S. Kovalev, K. V. Kladko, O. V. Usatenko
Subject area: Lattice dynamics and crystal statistics.
1995 Volume 64 Issue 7 Pages
2455-2464
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
Soliton-like excitations with frequencies in the gap and near the gap of linear spectrum are considered for diatomic chain with small mass difference. The chains with the additional quartic anharmonic potential of nearest-neighbor interaction and quartic nonlinear interaction with external elastic substratum (on-site potential) are studied. It is shown that the localized excitations represent the complicated combination of solitons of acoustic and quasi-optical branches of the spectrum. Gap solitons are studied with the help of the methods of qualitative analysis of dynamical systems and of the method of asymptotical expansions. It is shown that when the frequency of soliton changes a number of bifurcations of the soliton solutions takes place. The bifurcation picture is different for different forms of nonlinearity in diatomic chain and depend on relation between nonlinear interaction constants. Solitons with the frequencies out of the gap have the form of bound state of “ bright'' and “ dark'' solitons or dark soliton and soliton on the pedestal.
View full abstract
-
Tomozo Tomoyose, Tatsuhiro Yogi, Michisuke Kobayashi
Subject area: Lattice dynamics and crystal statistics.
1995 Volume 64 Issue 7 Pages
2465-2469
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
A frequency and wave vector dependent dielectric function of α -AgI is studied by using a phonon description based on a modified Hubbard-Beeby theory. The frequency dependent dielectric function is characterized by a main LO phonon peak and a sub LA phonon peak. The frequency spectrum for the dielectric function is consistent with those for the ac conductivity and the charge density dynamical structure factor of α -AgI.
View full abstract
-
A. Craido
Subject area: Lattice dynamics and crystal statistics.
1995 Volume 64 Issue 7 Pages
2470-2477
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
An intermolecular semiempirical 6-exp potential model has been used to calculate the lattice dynamics of 4-4'-dichlorodiphenylsulphone allowing for molecular flexibility with three internal degrees of freedom which are taken into account using an intramolecular potential function. The calculated Raman and infrared frequencies are in agreement with the available experimental data and the analysis of the polarization vectors allows us to characterize the experimental spectra. A soft-mode branch with a minimum at q=0.80, b
* appears which could explain the transition to the incommensurate phase where the modulation can be described with a wave vector of 0.78, b
* at 90, K. The soft-mode eigenvector is compared with the modulation displacements of the incommensurate phase and the influence of the anticrossing behaviour which shows the soft branch near its minimum is discussed.
View full abstract
-
Wilson Agerico Diñno, Hideaki Kasai, Ayao Okiji
Subject area: Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties).
1995 Volume 64 Issue 7 Pages
2478-2487
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
Recent time-of-flight experiments show a non-monotonous dependence of the dissociative adsorption/sticking
* probability of D
2(H
2)/Cu(111) on the initial rotational state. There is an observed decrease in the sticking probability with a slight increase in the initial rotational state quantum number j. As j is increased further, the sticking probability eventually increases. We show that, to account for this interesting behaviour, there are two opposing factors working for and against the adsorption process: STEERING EFFECT and ENERGY TRANSFER EFFECT. The first is dueto a dynamical reorientation of the molecule, and the latter is due to the coupling of therotational motion to the translational motion along the reaction path. To illustrate these two effects, we performed quantum mechanical model calculations using a variation of the coupled-channel method, a physically realistic model potential based on available potential energy (hyper-) surface plots for D
2(H
2)/Cu for two different orientations-parallel and perpendicular to the surface, and the concept of a reaction path.
View full abstract
-
Taka–hisa Arima, Yoshinori Tokura
Subject area: Electron states in condensed matter.
1995 Volume 64 Issue 7 Pages
2488-2501
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
Optical study of trivalent 3d transition metal oxide compounds RMO
3 with perovskite-type structure has revealed the variation of their electronic structures with the 3d element M and rare earth element R. The low energy feature is governed by electronic states in the M-O network. The charge gap, either of the Mott type or charge-transfer type, is observed for a series of RMO
3 compounds, except for metallic LaNiO
3 and LaCuO
3 compounds. The charge gap systematics has been accounted for in terms of a simple ionic model. However, the deviation from the ionic model is magnified in narrow gap compounds, where the M, 3d-O, 2p mixing appears to reshuffle the electronic states. The variation of the covalent nature of the M-O network in the RMO
3 compounds is also discussed in terms of the shell-model analysis of the phonon spectra.
View full abstract
-
Hiroyuki Tajima, Shuuji Aonuma, Hiroshi Sawa, Reizo Kato
Subject area: Electron states in condensed matter.
1995 Volume 64 Issue 7 Pages
2502-2509
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
The temperature dependence of polarized infrared reflectance spectra was investigated on the single crystal of (Me
2DCNQI-d
7)
2Cu whose electrical resistivity was continuously monitored by the four-probe method. Above 77, K, the resistivity decreases on lowering the temperature, and the reflectance spectra exhibit Drude-like dispersion for both polarizations parallel and perpendicular to the crystallographic c-axis. Between 77, K and 75, K, the resistivity increases more than 10
6 times that of 77, K, and the reflectance spectra exhibit drastic change suggesting dimensionality crossover from a three-dimensional conductor into a one-dimensional insulator. Based on the reflectivity data it was concluded that the metal-insulator transition in this salt is accompanied by discontinuous formation of CDW.
View full abstract
-
Chikara Sugiura
Subject area: Electron states in condensed matter.
1995 Volume 64 Issue 7 Pages
2510-2523
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
The P Kβ emission spectra in fluorescence from red amorphous phosphorus, 3d transition-metal phosphides TiP, CrP, FeP, Fe
2P, Fe
3P, CoP, Co
2P, Ni
5P
4, Ni
2P, Ni
3P, Cu
3P, ZnP
2 (black) and Zn
3P
2, and the semiconducting phosphides of the III-V type, BP, AlP, GaP and InP are measured with a high-resolution two-crystal vacuum spectrometer equipped with Ge(111) crystals. The influence of the metal atoms appears distinctly on the P Kβ fluorescence emission spectra. The measured spectra are compared with available X-ray emission and XPS valence-band spectra and theoretical energy-band calculations on a common energy scale. It is shown that considerable p-d, s mixing occurs in the valence bands of the 3d transition-metal phosphides and the P 3p states mix fairly with the P 3s states in the valence bands of red phosphorus, Gap and InP
View full abstract
-
Guo–qing Zheng, Yoshio Kitaoka, Kenji Ishida, Kunisuke Asayama
Subject area: Electron states in condensed matter.
1995 Volume 64 Issue 7 Pages
2524-2532
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
The hole numbers at Cu and oxygen sites in the CuO
2 plane in a wide variety of high-T
c materials have been extracted from the measured nuclear quadrupole frequency, ν
Q. The hole number in the Cu-3d
x2-y2 orbit, n
x2-y2, is found to be more than 0.85 in La
2-xSr
xCuO
4 (x=0.075-- 0.24), while decreases to 0.74 in Tl
2Ba
2Ca
2Cu
3O
10. Thus estimated n
x2-y2 is supported by the result that the orbital Knight shift along the c-axis, K
corb, increases in proportion to n
x2-y2. In contrast to the decrease of n
x2-y2, the hole number in the O-2p
σ orbit, n_p
σ, increases in going from the La- to the Tl-systems. It has been found that T
c is determined by two parameters about holes, i.e., n
x2-y2+2n_p
σ and n
x2-y2/2n_p
σ . The former tells the microscopic “ doping level'' of the CuO
2 plane, while a smaller n
x2-y2/2n_p
σ results in a weaker antiferromagnetic spin fluctuations of low energy. It has been found that not only a proper n
x2-y2+2n_p
σ but also a sufficiently small n
x2-y2/2n_p
σ (~= 1) are needed to obtain a high value of T
c.
View full abstract
-
Izumi Hase, Naoki Shirakawa, Yoshikazu Nishihara
Subject area: Electron states in condensed matter.
1995 Volume 64 Issue 7 Pages
2533-2540
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
The electronic energy band structures for BaNiS
2 and BaCoS
2, which are considered as highly correlated layered structure systems, have been calculated by using the scalar-relativistic full-potential linearized augmented plane wave (FLAPW) method within the local-density approximation. The result of the calculation suggests that both compounds are compensated metals. It is found that the calculated Fermi surfaces of both compounds have three-dimensional characters.
View full abstract
-
Yasumasa Hasegawa
Subject area: Electron states in condensed matter.
1995 Volume 64 Issue 7 Pages
2541-2549
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
In the presence of the magnetic field the quasi-one dimensional system with the open fermi surface is essentially one dimensional. In the one-dimensional picture the effective interaction is shown to depend on the magnetic field and the two-dimensional momentum. The amplitude of the effective interaction depends on the magnetic field, resulting in the successive transitions to the field-induced spin density wave. The quantum Hall effect is explained by the momentum dependence of the effective interaction. The effect of the alternating potential is also studied.
View full abstract
-
Jun Takeda, Yoshiaki Kobayashi, Katsuaki Kodama, Hiroshi Harashina, Ma ...
Subject area: Electronic transport in condensed matter.
1995 Volume 64 Issue 7 Pages
2550-2557
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
Physical properties of quasi two-dimensional electrons of BaCo
1-xNi
xS
2 which exhibits the Mott metal-insulator transition are reported. Various anomalous behaviors which are similar to those of high-T
c Cu oxides have been found. It is suggested that these anomalies are induced in the metallic and magnetically correlated state without long range order and therefore with very strong low energy magnetic fluctuations. It remains unclear if the system exhibits a decreasing tendency of the electronic specific heat coefficient γ upon approaching the Mott insulating phase, which is one of the remarkable anomalous behaviors of high-T
c oxides. Superconductivity has not been found down to 1.4, K.
View full abstract
-
Keiko Matsubara, Ko Sugihara, Kiyoshi Kawamura
Subject area: Electronic transport in condensed matter.
1995 Volume 64 Issue 7 Pages
2558-2562
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
Temperature dependence of the in-plane electrical resistivity of graphite below 10, K is calculated using the Planck distribution of phonons. Theoretical curve well reproduces the observed result. Values of the electron-phonon coupling constants are re-determined so as to fit the theory to the experimental data.
View full abstract
-
Hiroyuki Oyanagi, Hidekazu Kimura, Takahito Terashima, Yoshichika Band ...
Subject area: Superconductivity.
1995 Volume 64 Issue 7 Pages
2563-2571
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
The temperature dependence of the local structure in epitaxial YBa
2Cu
3O
7-δ thin film has been studied by polarized extended X-ray absorption fine structure (EXAFS) on the Cu K-edge. The results suggest that the local lattice anomalies occur not only at T
c but also well above T
c. The mean-square relative displacements for the two out-of-plane Cu--O bonds (Cu1--O4, Cu2--O4) simultaneously increased at T
c. The in-plane Cu--O bonds showed the anomalous decrease of dynamical disorder below 120, K-- 1.5T
c followed by a sharp increase at T
c which saturates at lower temperature, consistent with other lattice anomalies or dynamical spin susceptibilities observed at -- 1.5T
c. These suggest that the anomaly in in-plane oxygen atom vibrations below 1.5T
c is caused by the coupling between lattice distortions and magnetic excitations. The correlated displacement of apical oxygen atoms may induce a bilayer coupling associated with a charge transfer.
View full abstract
-
Naoki Enomoto, Kazushige Machida
Subject area: Superconductivity.
1995 Volume 64 Issue 7 Pages
2572-2576
Published: July 01, 1995
Released on J-STAGE: October 01, 1999
JOURNAL
RESTRICTED ACCESS
We analyze theoretically a domain wall structure associated with time reversal symmetry breaking in an unconventional superconducting pairing function. The doubly degenerate states necessarily form domain wall boundary where two kinds of randomly created degenerate states meet in a sample, giving rise to spatially varied magnetic field across it and associated screening current along it. This non-uniform field yields the anomalous increase of the muon spin relaxation time recently observed in a heavy Fermion material UPt
3 below the second transition temperature.
View full abstract
