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The lattice dynamics for rock-paper-scissors games is related to population theories in ecology. In most cases, simulations are performed by local and global interactions. It is known in the former case that the dynamics is usually stable. We find two types of non-random distributions in the stationary state. One is a cluster formation of endangered species: when the density of a species approaches zero, its clumping degree diverges to infinity. The other is the strong aggregations of high-density species. Such spatial pattern formations play important roles in population dynamics.

The flux I 0 reflected at specular angles 45°–45° from the surface of glossy paper and the assumed value of its diffuse component I 2 defined experimentally are measured with a goniophotometer. The ratio of I 0 to I 2 is taken as a measure of gloss, and denoted by G N F according to an earlier paper of E. Fukushima. 1) For a series of machine glazed papers differing considerably in colour, the values of C N F are compared with the visual gradings of 36 Japanese observers, and a linear correlation of the logarithm of G N F with the visual gloss is found with a correlation coefficient +0.986 except for two papers. The method of determining the value of I 2 is also introduced and the voting distributions of the observers for the gloss of the papers are discussed.

The paraelectric-to-ferroelectric phase transformation of (NH 4 ) 2 Cd 2 (SO 4 ) 3 is conjectured to be caused by an instability of three degenerate pairs of conjugate lattice vibration modes with a wave length such that the condensation of each pair of conjugate waves should triple the primitive unit cell. This was explained in a previous paper with a model in which the spontaneous polarization vector arises parallel to the wave normal of the condensed soft waves. Reality of this model, however, seems difficult because of a certain severe requirement for its ferroelectricity. The present paper proposes a model in which P s arises perpendicular to the wave normal. This model implies no such severe requirement.

A recent argument against the validity of the Lorentz transformation in high energy hadronic collisions based on existing experimental data is examined by reanalysis of the same data in more compatible form. There is found to be no evidence of contradiction with special relativity.

In the previous paper of Koga of the same title its the present, the results are more or less different from those of Enskog and Chapman. At first sight, it seemed that the treatment of Enskog and Chapman might not be correct for lacking of interpretation of the physical meanings. But later we arrived at the conclusion: Enskog-Chapman's solution is correct formally, and further we can show that the variables adopted by them are of the same physical meanings as those in Koga's treatment. Although we cannot yet mention any mistake positively in Koga's results, yet some lacks necessary of verifications are found on Koga's side.

The semicircle theorems obtained by Howard and Gupta are generalized. A sufficient condition for the stability and a semicircular region for the complex rate of growth of unstable modes are obtained with reference to the situation discussed by them in §6. The dual role of the uniform axial magnetic field is manifested.

On affirme que les resultats de l'article donne dans le titre ne sont pas nouveaux et que leur interpretation est incorrecte

The report of a two-neutron state yield in deuteron irradiation of Al was investigated. Analysis of gamma spectra observed at various times after irradiation show no activity corresponding to the decay of Al29, which would have been produced in dineutron capture in Al27. None of the observed activities had the half life of the reportedly observed activity. (D.C.W.)

Some statistical properties of origami (the art of paper folding) are investigated. In a crease pattern of an origami work, a paper sheet is divided into many “cells” surrounded by creases. We compute the cell-size distributions of four origami works and find that they are described by the superposition of lognormal distributions with different averages and variances. This lognormal behavior can be explained by a successive-folding process that works as a multiplicative effect. To confirm this idea, we introduce a numerical model by only incorporating a successive-folding process, and discuss its analytical properties. Moreover, we show that a group-separation structure is also essential in origami, which is different from pure crumpling.

Recent progress of epitaxial graphene on SiC was reviewed, focusing on its growth and structural and electronic features. Homogeneous graphene can be grown on SiC(0001) on a wafer scale, however on SiC(\(000\bar{1}\)) multilayer but rotationally stacked graphene with monolayer like electronic property grows. HRTEM revealed the formation mechanism and structural features of graphene on the both surfaces. The high structural and electronic quality of the grown graphene is monitored by Raman spectroscopy and magneto-transport characterization. High-resolution ARPES measurements of the electronic dispersion around the \(\bar{\text{K}}\)-point retrieved the ABA and ABC stacked trilayer graphene. The measurements also directly revealed that electronic structures of graphene were manipulated by transfer doping and atomic intercalation. In particular, p- and n-doped regions on a meso-scale and the p–n junctions prepared on SiC via controlling intercalation of Ge exhibited ballistic transport and Klein tunneling, ...

The decay of 24 min 146 Pr has been studied with Ge(Li), pure Ge, NaI(Tl) and plastic detectors in singles and coincidence modes. Sources were prepared by the chemical separation, called a rapid paper electrophoresis, from the fission products of 235 U. A total of 104 γ-ray transitions, 64 of them not reported before, have been observed and 88 transitions of them are incorporated into a level scheme comprising 32 excited states of 146 Nd. Observed Q β value was 4.15±0.15 MeV. Gamma-gamma directional angular correlation measurements in 146 Nd have been performed with 12 cascades each including 453.9 keV 2 + →0 + ground state transition. Spin assignments of 13 levels in 146 Nd were deduced. The low lying-states in 146 Nd are discussed in terms of the quasi band.

The decay of a short lived nucleus 144 La to levels of 144 Ce was investigated with Ge(Li), NaI(Tl) and plastic detectors in singles and coincidence modes. Radioactive sources were prepared by the chemical separation, a rapid paper electrophoresis, from the fission products of 235 U. The half-life of 144 La is 40.6 ±1.0 sec. Fifty-four γ-rays, including 17 new ones, were observed and 46 of them are incorporated in a decay scheme of 144 La including 11 new levels. The Q β value was deduced to be 4.3 ±0.1 MeV on the basis of the results of the γ- β coincidence measurements.

We have calculated the thermoelectric conductivity tensor $\varepsilon_{ij}$ and the thermal conductivity tensor $\lambda_{ij}$ of a unidirectional lateral superlattice (ULSL) ($i,j = x,y$, with the $x$-axis aligned to the principal axis of the ULSL), %, given as the first- and the second-order moments, employing based on the asymptotic analytic formulas of the electrical conductivity tensor $\sigma_{ij}$ in the literature valid at low magnetic fields where large numbers of Landau levels are occupied. With the resulting analytic expressions, we clarify the conditions for the Mott formula (Wiedemann-Franz law) to be applicable with high precision to $\varepsilon_{ij}$ ($\lambda_{ij}$). We further present plots of the commensurability oscillations $\delta\varepsilon_{ij}$, $\delta\lambda_{ij}$, $\delta\kappa_{ij}$, and $\delta S_{ij}$ in $\varepsilon_{ij}$, $\lambda_{ij}$, (an alternative, more standard definition of) the thermal conductivity tensor $\kappa_{ij}$, and the thermopower tensor $S_{ij}$, calculated using typical parameters for a ULSL fabricated from a GaAs/AlGaAs two-dimensional electron gas (2DEG). Notable features of the $\delta S_{ij}$ are (i) anisotropic behavior ($\delta S_{xx} \ne \delta S_{yy}$) and (ii) the dominance of the $xy$ component over the other components ($|\delta S_{xy}| \gg |\delta S_{yx}|, |\delta S_{xx}|, |\delta S_{yy}|$). The latter clearly indicates that the two Nernst coefficients, $S_{xy}$ and $S_{yx}$, can be totally different from each other in an anisotropic system. Both (i) and (ii) are at variance with the previous theory and are attributable to the inclusion of a damping factor due to the small-angle scattering characteristic of GaAs/AlGaAs 2DEGs, which have not been taken into consideration in $\delta S_{ij}$ thus far., Comment: 14 pages, 9 figures, Title and Introduction altered to make the main point of the paper clearer. Minor revisions throughout the paper. Some additions to the IV Discussion. Explicit energy dependence of the zero-temperature conductivity newly presented in the Appendix

This review paper describes the basic concept and technical details of sparse modeling and its applications to quantum many-body problems. Sparse modeling refers to methodologies for finding a small number of relevant parameters that well explain a given dataset. This concept reminds us physics, where the goal is to find a small number of physical laws that are hidden behind complicated phenomena. Sparse modeling extends the target of physics from natural phenomena to data, and may be interpreted as "physics for data". The first half of this review introduces sparse modeling for physicists. It is assumed that readers have physics background but no expertise in data science. The second half reviews applications. Matsubara Green's function, which plays a central role in descriptions of correlated systems, has been found to be sparse, meaning that it contains little information. This leads to (i) a new method for solving the ill-conditioned inverse problem for analytical continuation, and (ii) a highly compact representation of Matsubara Green's function, which enables efficient calculations for quantum many-body systems., Comment: 24 pages, 32 figures, to be published in J. Phys. Soc. Jpn. as an invited review paper

In this paper we review the physical relevance of a Korteweg-de Vries (KdV) equation with higher-order dispersion terms which is used in the applied sciences and engineering. We also present exact traveling wave solutions to this generalized KdV equation using an elliptic function method which can be readily applied to any scalar evolution or wave equation with polynomial terms involving only odd derivatives. We show that the generalized KdV equation still supports hump-shaped solitary waves as well as cnoidal wave solutions provided that the coefficients satisfy specific algebraic constraints. Analytical solutions in closed form serve as benchmarks for numerical solvers or comparison with experimental data. They often correspond to homoclinic orbits in the phase space and serve as separatrices of stable and unstable regions. Some of the solutions presented in this paper correct, complement, and illustrate results previously reported in the literature, while others are novel., 12 pages, 4 figures, minor text modifications, updated bibliography

We study self-propelled particles by direct numerical simulation of the nonlinear Kramers equation for self-propelled particles. In our previous paper, we studied self-propelled particles with velocity variables in one dimension. In this paper, we consider another model in which each particle exhibits directional motion. The movement direction is expressed with a variable $\phi$. We show that one-dimensional solitary wave states appear in direct numerical simulations of the nonlinear Kramers equation in one- and two-dimensional systems, which is a generalization of our previous result. Furthermore, we find two-dimensionally localized states in the case that each self-propelled particle exhibits rotational motion. The center of mass of the two-dimensionally localized state exhibits circular motion, which implies collective rotating motion. Finally, we consider a simple one-dimensional model equation to qualitatively understand the formation of the solitary wave state., Comment: 9 pages, 8 figures

We have proposed the energy landscape transformation of Ising problems (ELTIP), which changes the combination of the state and eigenvalue without changing all the original eigenvalues [arXiv:2202.05927]. We study how the ELTIP affects the anti-crossing between two levels of the ground and first excited states during quantum annealing. We use a 5-spin maximum-weighted independent set for the problem to numerically investigate the anticrossing. For comparison, we introduce a non-stoquastic Hamiltonian that adds antiferromagnetic interaction to the normal transverse magnetic field. Annealing with the non-stoquastic Hamiltonian is effective for difficult problems. The non-stoquastic Hamiltonian mitigates the anti-crossing when only the energy gap between the ground state and the first excited state of the final state is small. When the ELTIP is used, the anti-crossing disappears. For the problems investigated in this paper, the ELTIP shortens the annealing time to guarantee adiabatic change more than the non-stoquastic Hamiltonian.

We have extended dynamic scaling hypothesis to describe the wide range of experiments on growing rough interfaces. An alternative approach of original Family–Vicsek scaling hypothesis was not successfully applied to the growing interfaces of paper wetting in that we obtained unphysical values of roughness exponents. Since very nice data collapse suggested the existence of some kind of dynamic scaling, we have tried to extend the dynamic scaling hypothesis. It was found that the extended dynamic scaling hypothesis can be nicely applied to the growing rough interfaces in paper wetting, yielding values of roughness and growth exponents α≃0.73, β≃0.60, respectively.

In this paper recent substantial progress in applying the density-matrix renormalization-group (DMRG) to the simulation of the time-evolution of strongly correlated quantum systems in one dimension is reviewed. Various approaches to generating a time-evolution numerically are considered. The key focus of this review is on current strategies to circumvent the limitations of the quite small subspace well approximated by DMRG, by either enlarging or changing it as time evolves. All these approaches can be extended to the simulation of mixed, i.e. finite-temperature states. While this paper is phrased almost entirely in standard DMRG language, I finish by considering the alternative formulation of time-evolutions in the language of matrix product states which is less well-known but conceptually more powerful.

We report the specific heat of single crystals of the spin ice compound Dy$_2$Ti$_2$O$_7$ at temperatures down to 100 mK in the so-called Kagome ice state. In our previous paper, we showed the anisotropic release of residual entropy in different magnetic field directions and reported new residual entropy associated with spin frustration in the Kagome slab for field in the [111] direction. In this paper, we confirm the first-order phase transition line in the field-temperature phase diagram and the presence of a critical point at (0.98 T, 400 mK), previously reported from the magnetization and specific-heat data. We newly found another peak in the specific heat at 1.25 T below 0.3 K. One possible explanation for the state between 1 T and 1.25 T is the coexistence of states with different spin configurations including the 2-in 2-out one (Kagome ice state), the 1-in 3-out state (ordered state) and paramagnetic one (free-spin state)., Comment: 14 pages, 7 figures

The trapezoidal rule has often been referred to as being symmetric or time-reversible and is therefore good for Hamiltonian systems. However, it is well-known that the trapezoidal rule is not symplectic, but is related to the mid-point rule (which is symplectic) through a coordinate transformation. In this paper, we show that the trapezoidal rule preserves a symplectic structure different from the original one by O ( h 2 ). The ideas in this paper also motivate us to apply Richardson's extrapolation to the trapezoidal rule. Numerical results show that the extrapolated trapezoidal rule preserves the Hamiltonian up to O ( h 4 ).

We have proposed, in our previous papers, a method to characterize integrable discrete soliton equations. In this paper we generalize the method further and obtain a $q$-difference Toda equation, from which we can derive various $q$-difference soliton equations by reductions., Comment: 21 pages, 4 figure, epsfig.sty

In recent papers we demonstrated a new class of barrier tunneling phenomena which can be observed in periodically driven one dimensional barrier systems (i.e., 1.5D barrier tunneling systems). In such systems the tunneling component is in general accompanied by remarkable interference fringe patterns as the perturbation strength exceeds a certain characteristic value. Such a phenomenon is quite general and is not restricted to periodically driven 1D systems, and it may be also observed in intrinsic two dimensional autonomous systems. The complex-domain semiclassical theory developed by ourselves was applied to the problem, and we succeeded in reconstructing every detail of the fringed tunneling wavefunction only by using the complexified classical tunneling trajectories. This fact greatly motivates us to investigate the mechanism of the tunneling in terms of “classical mechanics”. The later part of the present paper is devoted to asserting the generality of the “classical mechanism” of the fringed tunneli...

Notion of square-root topological insulators have been recently generalized to higher-order topological insulators. In two-dimensional square-root higher-order topological insulators, emergence of in-gap corner states are inherited from the squared Hamiltonian which hosts higher-order topology. In this paper, we propose that the martini lattice model serves as a concrete example of higher-order topological insulators. Furthermore, we also propose a suquare-root higher-order topological insulator based on the martini model. Specifically, we propose that the honeycomb lattice model with two-site decoration, whose squared Hamiltonian consists of two martini lattice models, realizes square-root higher-order topological insulators. We show, for both of these two models, that in-gap corner states appear at finite energies and that they are portected by non-trivial bulk $\mathbb{Z}_3$ topological invariant., Comment: 10 pages, 10 figures

For searching a new chemical material which satisfies the target characteristic value, for example emission wavelength, many cut and trial of experiments/calculations are required since the chemical space is astronomically large (organic molecules generates >10^60 candidates). Extracting feature importance is a method to reduce the chemical space, and limiting the search space to those features leads to shorter development time. Quantum computer can generate sampling data faster than classical computers, and this property is utilized to extract feature importance. In this paper, quantum annealer was used as a sampler to make data for extracting feature importance of material properties. By screening the chemical space with feature importance, it was found that the chemical space can be reduced to less than 1 percent. This result suggests that the acceleration of material research can be achievable.

In the previous paper, we studied the random-mass Dirac fermion in one dimension by using the transfer-matrix methods. We furthermore employed the imaginary vector potential methods for calculating the localization lengths. In particular, we investigated effects of the nonlocal but short-range correlations of the random mass. In this paper, we shall study effects of the long-range correlations of the random mass especially on the delocalization transition and singular behaviors at the band center. We calculate localization lengths and density of states for various nonlocally correlated random mass. We show that there occurs a “phase transition” as the correlation length of the random Dirac mass is varied. The Thouless formula, which relates the density of states and the localization lengths, plays an important role in our investigation.

The purpose of this paper is to present a new general approach to solve ground-state energies of the double-electron systems in a uniform magnetic field, in which the basic element of evolution is the set in the solution space, rather than the point. The paper defines the Cell Evolutionary Algorithm, which implements such a view of the evolution mechanism. After we get the optimal set in which the optimal solution may be, then this approach applies the embedded search method to obtain the optimal solution. We tested this approach on atomic structure, and results show that it can improve not only the efficiency but also the accuracy of the calculations as they relate to this specific problem.

The three-dimensional Anderson model is a well-studied model of disordered electron systems that shows the delocalization--localization transition. As in our previous papers on two- and three-dimensional (2D, 3D) quantum phase transitions [J. Phys. Soc. Jpn. {\bf 85}, 123706 (2016), {\bf 86}, 044708 (2017)], we used an image recognition algorithm based on a multilayered convolutional neural network. However, in contrast to previous papers in which 2D image recognition was used, we applied 3D image recognition to analyze entire 3D wave functions. We show that a full phase diagram of the disorder-energy plane is obtained once the 3D convolutional neural network has been trained at the band center. We further demonstrate that the full phase diagram for 3D quantum bond and site percolations can be drawn by training the 3D Anderson model at the band center., 11 pages, 5 figures. Published version

This paper quantitatively discusses the effect of positive nuclear track potentials on the motion of secondary electrons due to heavy-ion irradiation using a simulation model. This model reproduces the tendency of measurement of the number of secondary electrons. Using this model, physical phenomena can be treated closer to reality than those using the conventional models. Here, the track potential is defined as the potential formed from the electric field near the track of a heavy ion. This effect is expected to be given as functions of not only the mean paths (τ) between incident ion impact ionization events but also the average initial secondary electron energies. The results shown in this paper indicate that the effect of the track potential is mainly determined by τ.

In a recent article [Yamamoto and Ikuta: J. Phys. Soc. Jpn. 68 (1999) 2602] state that the true origin of negative differential conductivity (NDC) has never been shown, in apparent contradiction of claims made in earlier papers [Z. Lj et al. .: Aust. J. Phys. 37 (1984) 23; R. E. Robson: ibid. 37 (1984) 35]. In the present paper, we argue that the true origin of NDC has indeed been explained satisfactorily, and present a comprehensive range of calculations for a number of cases, demonstrating the effectiveness of momentum transfer theory [ Hot electron transport in semiconductors (Springer, Berlin, 1985) p. 82] for understanding NDC from both a qualitative and quantitative perspective.

In a previous paper [M. Matsushita and T. Ohta: J. Phys. Soc. Jpn. 67 (1998) 1973], the model equation for a structural phase transition between a hexagonal symmetry and a square symmetry has been introduced and numerical simulations have been carried in two dimensions where the order parameter is a non-conserved quantity. In the present paper, we extend the model equation for the conserved order parameter. The thermal random force is also taken into account. The kinetics of the structural transition is studied by analyzing the non-equilibrium scattering function of the domain structures and by evaluating the time-dependence of the volume fraction of one of the structures. The equilibrium phase diagram for domain structures is also derived by means of the single wave number approximation.