著者
Shunji Sugai Nobuyuki Kaji Akihito Osuka Koshi Takenaka Shigeru Horii Hiroshi Ikuta
出版者
THE PHYSICAL SOCIETY OF JAPAN
雑誌
Journal of the Physical Society of Japan (ISSN:00319015)
巻号頁・発行日
vol.74, no.3, pp.871-874, 2005-03-15 (Released:2007-12-06)
参考文献数
26

Optical reflection spectroscopy perpendicular to the double-chain of PrBa2Cu4O8 clarified that carriers in the plane transfer to the chain almost completely as temperature decreases from 295 to 150 K. Many anomalies around 150 K can be explained by the transfer of carriers. The temperature and Zn substitution effects suggest that the chains are in the Fermi liquid state when the carrier density is close to 0.5/Cu(1) and in the Tomonaga–Luttinger liquid state when the carrier density is 0.4/Cu(1).
著者
Kazuki Nakanishi Macoto Kikuchi
出版者
THE PHYSICAL SOCIETY OF JAPAN
雑誌
Journal of the Physical Society of Japan (ISSN:00319015)
巻号頁・発行日
vol.75, no.6, pp.064803, 2006-06-15 (Released:2009-08-27)
参考文献数
17
被引用文献数
4

We investigate aggregation mechanism of two proteins in a thermodynamically unambiguous manner by considering the finite size effect of free energy landscape of HP lattice protein model. Multi-self-overlap-ensemble Monte Carlo method is used for numerical calculations. We find that a dimer can be formed spontaneously as a thermodynamically stable state when the system is small enough. It implies the possibility that the aggregation of proteins in a cell is triggered when they are confined in a small region by, for example, being surrounded by other macromolecules. We also find that the dimer exhibits a transition between unstable state and metastable state in the infinite system.
著者
Hoshino Sadao Fujii Yasuhiko Harada Jimpei Axe J. D.
出版者
一般社団法人 日本物理学会
雑誌
Journal of the Physical Society of Japan (ISSN:00319015)
巻号頁・発行日
vol.41, no.3, pp.965-973, 1976
被引用文献数
54

Phonon dispersion relations of CuBr having zincblende-type structure were measured by the neutron inelastic scattering technique with a triple-axis spectrometer. The dispersion curves measured at 77 K were well described by the shell model with 14 parameters which has been successfully applied to explain the data for GaAs, GaP and InSb. The elastic constants were obtained both from sound velocities estimated from the initial slopes of acoustic phonon dispersion curves and from the shell-model-fit. The optical phonon energies at the zone center are in good agreement with the Raman scattering data. The temperature dependence of phonon scattering was also measured. It was found that the phonon energies as well as the shape of phonon peaks varied considerably with temperature, suggesting that the effect of anharmonicity is remarkable in CuBr even at room temperature.
著者
Koikegami Shigeru Fujimoto Satoshi Yamada Kosaku
出版者
一般社団法人日本物理学会
雑誌
Journal of the Physical Society of Japan (ISSN:00319015)
巻号頁・発行日
vol.66, no.5, pp.1438-1444, 1997-05-15
被引用文献数
14 56

The dressed d-electron Green's function of the d-p model is computed self-consistently based onthe fluctuation-exchange approximation. Using this Green's function and assuming the d.c .2synametry for the rnotnentum dependence of the gap ftrnction, we obtain the reasonable super-conducting transition temperature T. in the several cases where the d-(p-)hole number is close tothe experimental value of La).75Srg.z,jCuO,j based on NMR/NQR analyses. Using this Green'sfunction, we calctrlate the d-electron spin strsceptibility, which has very sharp incounrnensuratepeaks near T. for the low frequency as observed in neutron scattering data on L2lL1.86SI0.14CVlO4.The qtuasi-particle excitation spectrum in the normal state near T. is also obtained frorn thisGreen's function. The energy dispersion of quasi-particles near the Fermi level is alrnost flataround the (m/a,O) point. This electronic structure is due to many-body effects, rather thanbeing induced by band effects.
著者
Nojiri Hiroyuki Ohta Hitoshi Okubo Susumu FUJITA Osamu AKIMITSU Jun MOTOKAWA Mitsuhiro
出版者
一般社団法人日本物理学会
雑誌
Journal of the Physical Society of Japan (ISSN:00319015)
巻号頁・発行日
vol.68, no.10, pp.3417-3423, 1999-10-15
被引用文献数
49

Transitiotts T.cetxveen the grotund singlet state ;ttad tlne excited tr'ij.c1et st?tte ll2lV6 Toeeta o].cser'vedin CtrGe0a Icy l11C2ll1S of' strbutaillitaaeter XV2lV6 electrout sj.cira I'CSOI12tl1CC. Tl?e energy :211) at zerofield is evalvrated to loe 570GHz (2.36 taaeV) artad this X'21lLlC is rtearrly ideuaticatl to tlae gulp at tlaezone center olvserved Joy inelststic netrtrota scatteritag. Tlae txlcsorptiota irxterxsityr shoxvs strongfield orient?ttion dejcenudetace, l,>tut it shoxx's [10 sigrrific?rnt depermdence 011 tta?tgnetic field itatensity.These f'eattrres hax'e 1,>een expl;tir?ed Joy cotasidering tlae existence of' Dzystloslainsky-lV[oriya (DIXI)anLisyta'nutaetric exch;ttage inter?rctiora. Tlae doj.cing effect 011 this siraglet-trijclet excitattion h?rs beetaalso stv-rdied. A dr?xstic lcr'oadexairxg of the ?x1osor'ptiot? line is observed by tlae doping of only 0.5'/o of' 81.
著者
Hori Nanako Yamada Akko Oshiro Yuki SANO Osamu
出版者
一般社団法人日本物理学会
雑誌
Journal of the Physical Society of Japan (ISSN:00319015)
巻号頁・発行日
vol.76, no.2, pp."024401-1"-"024401-7", 2007-02-15
被引用文献数
1 7

An experimental study is made on the pattern formation of the sand bed immersed in a viscous fluid between two concentric cylinders of finite depth, whose channel width is sufficiently large as compared with the particle size. The upper boundary of the fluid is in contact with an annular ring made of transparent acrylic resin, which slides itself at a constant angular velocity, whereas other boundaries are at rest. The velocity field is measured, which revealed that the vertical velocity profile is quite different from the linear shear flow, whereas the effect of the side walls is not significant in the bulk region of our channel. The onset and growth of barchan dunes and sand ripples, time variation of the wavelength and volume of the ripples, and their dependence on the fluid velocity are examined. A simple model that describes the growth of the ripples is proposed.
著者
Hasegawa Kouhei Lim Chong-Sa Maru Nobuhito
出版者
The Physical Society of Japan
雑誌
Journal of the Physical Society of Japan (ISSN:00319015)
巻号頁・発行日
vol.85, no.7, pp.74101-1-12, 2016-06-10
被引用文献数
3

In the gauge-Higgs unification with multiple extra spaces, the Higgs self-coupling is on the order of <italic>g</italic><sup>2</sup>and the Higgs boson is predicted to be light, being consistent with the LHC results. When the gauge group is simple, the weak mixing angle is also predictable. We address a question on whether there exists a model of gauge-Higgs unification in six-dimensional space-time, which successfully predicts the mass ratios of the Higgs boson and weak gauge bosons. First, using a useful formula, we give a general argument on the condition for obtaining a realistic prediction of the weak mixing angle sin<sup>2</sup>θ<sub>W</sub>= 1/4, and find that triplet and sextet representations of the minimal SU(3) gauge group lead to the realistic prediction. Concerning the Higgs mass, we notice that, in the models with one Higgs doublet, the predicted Higgs mass is always the same: <italic>M</italic><sub>H</sub>= 2<italic>M</italic><sub>W</sub>. However, by extending our discussion to the models with two Higgs doublets, the situation changes: we obtain an interesting prediction <italic>M</italic><sub>H</sub>≤ 2<italic>M</italic><sub>W</sub>at the leading order of the perturbation. Thus, it is possible to recover the observed Higgs mass, 125 GeV, for a suitable choice of the parameter. The situation is in clear contrast to the case of the minimal supersymmetric standard model, where <italic>M</italic><sub>H</sub>≤ <italic>M<sub>Z</sub></italic>at the classical level and the predicted Higgs mass cannot recover the observed value.
著者
Hasegawa Kouhei Lim Chong-Sa Maru Nobuhito
出版者
The Physical Society of Japan
雑誌
Journal of the Physical Society of Japan (ISSN:00319015)
巻号頁・発行日
vol.85, no.7, pp.74101-1-12, 2016-06-10
被引用文献数
3

In the gauge-Higgs unification with multiple extra spaces, the Higgs self-coupling is on the order of <italic>g</italic><sup>2</sup>and the Higgs boson is predicted to be light, being consistent with the LHC results. When the gauge group is simple, the weak mixing angle is also predictable. We address a question on whether there exists a model of gauge-Higgs unification in six-dimensional space-time, which successfully predicts the mass ratios of the Higgs boson and weak gauge bosons. First, using a useful formula, we give a general argument on the condition for obtaining a realistic prediction of the weak mixing angle sin<sup>2</sup>θ<sub>W</sub>= 1/4, and find that triplet and sextet representations of the minimal SU(3) gauge group lead to the realistic prediction. Concerning the Higgs mass, we notice that, in the models with one Higgs doublet, the predicted Higgs mass is always the same: <italic>M</italic><sub>H</sub>= 2<italic>M</italic><sub>W</sub>. However, by extending our discussion to the models with two Higgs doublets, the situation changes: we obtain an interesting prediction <italic>M</italic><sub>H</sub>≤ 2<italic>M</italic><sub>W</sub>at the leading order of the perturbation. Thus, it is possible to recover the observed Higgs mass, 125 GeV, for a suitable choice of the parameter. The situation is in clear contrast to the case of the minimal supersymmetric standard model, where <italic>M</italic><sub>H</sub>≤ <italic>M<sub>Z</sub></italic>at the classical level and the predicted Higgs mass cannot recover the observed value.
著者
Teruya Atsushi Suzuki Fuminori Aoki Dai Honda Fuminori Nakamura Ai Nakashima Miho Amako Yasushi Harima Hisatomo Hedo Masato Nakama Takao Onuki Yoshichika
出版者
The Physical Society of Japan
雑誌
Journal of the Physical Society of Japan (ISSN:00319015)
巻号頁・発行日
vol.85, no.6, pp.64716-1-10, 2016-06-01
被引用文献数
11

We succeeded in growing high-quality single crystals of the pyrite-type cubic compounds CoSe<sub>2</sub>and CoS<sub>2</sub>using the transport agent CoBr<sub>2</sub>and measured the electrical resistivity, specific heat, magnetic susceptibility, magnetization, and de Haas–van Alphen (dHvA) effect. We confirmed that CoSe<sub>2</sub>is an exchange-enhanced paramagnet revealing a broad maximum at around 50 K in the temperature dependence of the magnetic susceptibility. The electronic specific heat coefficient is moderately large, γ = 18 mJ/(K<sup>2</sup>·mol). On the other hand, CoS<sub>2</sub>is a ferromagnet with a Curie temperature <italic>T</italic><sub>C</sub>= 122 K and an ordered moment μ<sub>s</sub>= 0.93 μ<sub>B</sub>/Co. The γ of 21 mJ/(K<sup>2</sup>·mol) of CoS<sub>2</sub>is slightly larger than that of CoSe<sub>2</sub>. A large ordered moment, together with a large γ, is characteristic of CoS<sub>2</sub>because CoS<sub>2</sub>is a half-metallic spin state in the ferromagnetic state. Correspondingly, we detected a main dHvA branch with a large cyclotron effective mass of 13<italic>m</italic><sub>0</sub>in the dHvA experiments. The detected dHvA branches in CoS<sub>2</sub>and CoSe<sub>2</sub>are discussed on the basis of the results of energy band calculations, revealing a broken fourfold symmetry in the angular dependence of the dHvA frequency.
著者
Suzuki Masuo
出版者
一般社団法人日本物理学会
雑誌
Journal of the Physical Society of Japan (ISSN:00319015)
巻号頁・発行日
vol.61, no.9, pp.3015-3019, 1992-09-15
被引用文献数
1 123

A general scheme to realize nons)'xnmetric ltiglaer-order decompositio?t of exponen-tial operators and symplectic integrators is constructed. This gives a uxaif'?ed theory ofthe previous symnaetric and nons)'mmetric decomposition. Ruth's nccuasymmetricthird-order real decompositioxa is showta to be a simple example of tlae prcsent generaltheory.
著者
Kasuya Tadao Li Dexin
出版者
社団法人 日本物理学会
雑誌
Journal of the Physical Society of Japan (ISSN:00319015)
巻号頁・発行日
vol.66, no.6, pp.1587-1590, 1997
被引用文献数
8

Long-standing puzzling anomalous properties in Yb monopnictides are studied in detail with a novel new idea of paired Jahn-Teller distortion and charge dipolar ordering accompanied by compatible magnetic dipole ordering. The paired distortion occurs at around 50, K, commonly with an energy splitting of several meV. This is consistent with other systems that show similar paired Jahn-Teller distortion. Anomalous specific heat induced by level splitting, including the magnetic singlet ground state due to an antiferromagnetic pair exchange interaction, is observed as a two-peak structure with the lower peak around 5, K in common. A Néel transition at a low temperature of around 0.5, K in common is primarily a charge dipolar ordering due to pair ordering and occurs in competition with the pair singlet state, causing a weak transition with a small ordered moment. The above common features are caused by a strong-pair antiferromagnetic exchange interaction with nearly equal strengths.
著者
Harry Kojima Hidehiko Ishimoto
出版者
THE PHYSICAL SOCIETY OF JAPAN
雑誌
Journal of the Physical Society of Japan (ISSN:00319015)
巻号頁・発行日
vol.77, no.11, pp.111001, 2008-11-15 (Released:2011-12-28)
参考文献数
103
被引用文献数
10

Under applied magnetic field, the originally single superfluid 3He transition near 3 mK in zero field splits into two transitions between which a new A1 phase emerges. The two second order transitions are marked by abrupt changes in viscosity, zero sound attenuation and nuclear magnetic resonance. To date, the maximum magnetic field for producing A1 phase is 15 T. The A1 phase has been identified with a spin-polarized (ferromagnetic) superfluid system which breaks the relative symmetry between spin, orbit and gauge spaces. A superfluid mass current in A1 is simultaneously a spin current resulting in the propagation of spin-entropy wave. Experiments with spin-entropy wave provide measurements of anisotropic superfluid density and strong coupling parameters, spin diffusion coefficient and texture transformations. Owing to the spin-polarized nature, superflows may be generated by applied magnetic field gradients and measured from the induced magnetic fountain pressure. The mechanical spin density detector is developed to measure the spin relaxation in A1 phase. The observed unexpected temperature dependence of the spin relaxation time gives evidence that the A1 phase contains a small amount of the predicted minority spin condensate from dipolar interaction energy.
著者
柿中 晋治 梅野 健
出版者
Physical Society of Japan
雑誌
Journal of the Physical Society of Japan (ISSN:00319015)
巻号頁・発行日
vol.89, no.2, 2020-02-15

暗号通貨のビッグデータが持つ普遍的な統計則を発見 --「安定分布」と「キュービック則」による統一的な特徴付けに成功--. 京都大学プレスリリース. 2020-01-24.
著者
Kasaya Mitsuo Hihara Tadamiki Koi Yoshitaka
出版者
一般社団法人 日本物理学会
雑誌
Journal of the Physical Society of Japan (ISSN:00319015)
巻号頁・発行日
vol.34, no.1, pp.63-67, 1973
被引用文献数
22

Measurements of hyperfine field and quadrupole coupling of Co<SUP>59</SUP> have been made on the intermetallic compound Co<SUB>2</SUB>B. A large anisotropy in the hyperfine field is observed. The hyperfine fields along the local orthorhombic axes (<I>x</I>, <I>y</I>, and <I>z</I>) of the Co sites are &minus;53.7 kOe, &minus;83.1 kOe, and &minus;123.6 kOe, respectively, where the <I>z</I> axis is the two-fold axis which lies along the tetragonal &lang;110&rang; direction. The electric field gradients, |<I>q<SUB>xx</SUB></I>|, |<I>q<SUB>yy</SUB></I>|, and |<I>q<SUB>zz</SUB></I>|, are 1.43&times;10<SUP>24</SUP> cm<SUP>&minus;3</SUP>, 0.08&times;10<SUP>24</SUP> cm<SUP>&minus;3</SUP>, and 1.47&times;10<SUP>24</SUP> cm<SUP>&minus;3</SUP>, respectively. The charge distribution compatible with the observed electric field gradients suggests that the electronic states near the top of the band have a character of &psi;=&alpha;(3<I>z</I><SUP>2</SUP>&minus;<I>r</I><SUP>2</SUP>)+&beta;(<I>x</I><SUP>2</SUP>&minus;<I>y</I><SUP>2</SUP>).
著者
Pawan K. Tiwari G. J. H. Brussaard M. J. v. d. Wiel V. K. Tripathi
出版者
THE PHYSICAL SOCIETY OF JAPAN
雑誌
Journal of the Physical Society of Japan (ISSN:00319015)
巻号頁・発行日
vol.74, no.8, pp.2255-2259, 2005-08-15 (Released:2008-01-24)
参考文献数
23
被引用文献数
1

An indigenously built Ti:sapphire laser system delivering 50 mJ, 100 fs pulses at a repetition rate of 10 Hz, is employed to tunnel ionize air at 1 atm pressure and form a plasma channel. The laser is line focused using a cylindrical lens to a spot size of 20μm×1mm. A folded wave interferometry is used to deduce the radial electron density profile by measuring the phase shift and employing Abel inversion. The maximum value of chord-integrated electron density and radial electron density are estimated to be approximately equal to 3.0×1016 cm−2 and 4.0×1018 cm−3 respectively with density scale length of 20 μm. These results have been theoretically interpreted by developing a unified formalism of tunnel ionization. The experimental results are in reasonable agreement with the theory.