Refine your search:     
Report No.
 - 
Search Results: Records 1-20 displayed on this page of 21

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

Journal Articles

Novel field-induced quantum phase transition of the kagome-lattice antiferromagnet

Sakai, Toru; Nakano, Hiroki*

Journal of the Korean Physical Society, 63(2), p.601 - 604, 2013/08

 Times Cited Count:1 Percentile:12.72(Physics, Multidisciplinary)

The kagome-lattice antiferromagnet is investigated using the numerical exact diagonalization up to 42-spin clusters. From our investigation of the magnetization process, we found a novel field-induced quantum phase transition, called the "magnetization ramp", at 1/3 of the saturation magnetization. The finite-size scaling analysis of the critical exponents indicated a significant difference of the magnetization ramp from the magnetization plateau observed in the triangular-lattice antiferromagnet.

Journal Articles

$$^{29}$$Si-NMR study of antiferromagnet CeRh$$_2$$Si$$_2$$ using single crystals

Sakai, Hironori; Tokunaga, Yo; Kambe, Shinsaku; Matsumoto, Yuji; Matsuda, Tatsuma; Haga, Yoshinori

Journal of the Korean Physical Society, 63(3), p.352 - 355, 2013/08

 Times Cited Count:3 Percentile:30.06(Physics, Multidisciplinary)

$$^{29}$$Si-NMR Study of antiferromagnet CeRh$$_2$$Si$$_2$$ with a tetragonal ThCr$$_2$$Si$$_2$$-type structure has been performed using single crystals. The Knight shifts along the $$a$$ and $$c$$ axes have been measured as a function of temperatures in the paramagnetic state. At ambient pressure, the Knight shifts show the Ising-type anisotropy along the $$c$$ axis, which is similar to the magnetic susceptibility. The hyperfine coupling constants for $$^{29}$$Si along the $$a$$ and $$c$$ axes have been determined from Knight shifts versus static susceptibility plots.

Journal Articles

Magnetic phase diagram of UCoAl

Matsuda, Tatsuma; Tateiwa, Naoyuki; Yamamoto, Etsuji; Haga, Yoshinori; Onuki, Yoshichika; Aoki, Dai*; Flouquet, J.*; Fisk, Z.

Journal of the Korean Physical Society, 63(3), p.575 - 578, 2013/08

 Times Cited Count:4 Percentile:36.94(Physics, Multidisciplinary)

Journal Articles

Powder neutron diffraction study of HoCoGa$$_{5}$$

Kobayashi, Riki; Kaneko, Koji; Wakimoto, Shuichi; Chi, S.*; Sanada, Naoyuki*; Watanuki, Ryuta*; Suzuki, Kazuya*

Journal of the Korean Physical Society, 63(3), p.337 - 340, 2013/08

 Times Cited Count:3 Percentile:30.06(Physics, Multidisciplinary)

Journal Articles

Magnetic property in the ferromagnetic superconductor UGe$$_2$$ at pressures above the ferromagnetic critical pressure

Tateiwa, Naoyuki; Haga, Yoshinori; Matsuda, Tatsuma; Yamamoto, Etsuji; Onuki, Yoshichika; Fisk, Z.

Journal of the Korean Physical Society, 63(3), p.627 - 631, 2013/08

 Times Cited Count:0 Percentile:0(Physics, Multidisciplinary)

UGe$$_2$$ is a ferromagnet with the Curie temperature of 54 K at ambient pressure. The superconductivity appears in the pressure region of 1.0-1.6 GPa where UGe$$_2$$ is in the ferromagnetic state. Ferromagnetic state disappears above $$P_c$$ =1.6 GPa. In this study, we have measured the dc-magnetization up to 4.1 GPa using the ceramic anvil high pressure cell. We confirmed the maximum at $$T_{max}$$ in the temperature dependence of the dc magnetic susceptibility. With increasing pressure, $$T_{max}$$ is increased from 24 K at 1.9 GPa to 32 K at 2.6 GPa. The peak structure around $$T_{max}$$ becomes broader with increasing pressure and disappears above 4 GPa. The metamagnetic transition field $$H_m$$ increases rapidly with increasing pressure. We discuss the experimental results with the phenomenological spin-fluctuation theory.

Journal Articles

Shubnikov-de Haas oscillation in PuIn$$_3$$

Haga, Yoshinori; Bauer, E. D.*; Tobash, P. H.*; Mitchell, J. N.*; Ayala-Valenzuela, O.*; McDonald, R. D.*; Mielke, C. H.*; Fisk, Z.

Journal of the Korean Physical Society, 63(3), p.380 - 382, 2013/08

 Times Cited Count:3 Percentile:30.06(Physics, Multidisciplinary)

Journal Articles

Single crystal growth and physical properties of UT$$_2$$Al$$_{20}$$ (T = transition metal)

Matsumoto, Yuji; Matsuda, Tatsuma; Tateiwa, Naoyuki; Yamamoto, Etsuji; Haga, Yoshinori; Fisk, Z.

Journal of the Korean Physical Society, 63(3), p.363 - 366, 2013/08

 Times Cited Count:6 Percentile:47.11(Physics, Multidisciplinary)

Journal Articles

Optical conductivity of antiferromagnetic metallic chromium; Mean-field calculation for the multi-orbital Hubbard model

Sugimoto, Kodai*; Toyama, Takami*; Kaneshita, Eiji*; Tsutsui, Kenji

Journal of the Korean Physical Society, 63(3), p.632 - 635, 2013/08

 Times Cited Count:0 Percentile:0(Physics, Multidisciplinary)

Cr is the representative material of multi-orbital antiferromagnetism. We numerically calculate the band structure and density of states in commensurate antiferromagnetic Cr by multi-orbital Hubbard model with mean-field approximation. The result is adopted to the calculation of optical conductivity. The spectra of the optical conductivity is consistent with experimental data, and this promises the validity of our model.

Journal Articles

Real-time analysis of the spinmotive force due to domain wall motion

Ieda, Junichi; Maekawa, Sadamichi; Yamane, Yuta

Journal of the Korean Physical Society, 62(12), p.1802 - 1806, 2013/06

 Times Cited Count:2 Percentile:22.1(Physics, Multidisciplinary)

Spinmotive force, which is induced by motion of a nonuniform magnetic nanostructure, reflects real time dynamics of the magnetization texture. Using numerical simulations we study the spinmotive force associated with domain wall motion and find that its dc component scales with an applied magnetic field even in a field range where the wall motion is no longer associated with periodic angular rotation of the wall magnetization. As the field is increased, spikes in the voltage signals start to appear, which are mainly associated with vortex core nucleation and annihilation. At high fields, the slope of the generated dc voltage with the applied field is expected to be only dependent on the spin polarization of conduction electrons and thus can be used to accurately determine the degree of spin polarization in various materials.

Journal Articles

Linear-response theory of the longitudinal spin Seebeck effect

Adachi, Hiroto; Maekawa, Sadamichi

Journal of the Korean Physical Society, 62(12), p.1753 - 1758, 2013/06

 Times Cited Count:11 Percentile:61.98(Physics, Multidisciplinary)

Journal Articles

Heat and spin

Maekawa, Sadamichi; Adachi, Hiroto

Journal of the Korean Physical Society, 62(12), p.1985 - 1989, 2013/06

 Times Cited Count:0 Percentile:0(Physics, Multidisciplinary)

Journal Articles

Metal-insulator crossover accompanied by the dual nature of 5$$f$$ electrons with localized and itinerant charancters in $$beta$$-US$$_2$$

Metoki, Naoto; Sakai, Hironori; Yamamoto, Etsuji; Haga, Yoshinori; Matsuda, Tatsuma; Ikeda, Shugo*

Journal of the Korean Physical Society, 62(12), p.1782 - 1786, 2013/06

 Times Cited Count:1 Percentile:12.72(Physics, Multidisciplinary)

Magnetic excitation of a narrow gap semiconductor $$beta$$-US$$_2$$was studied by means of neutron scattering. At low temperatures clear crystalline electric field (CEF) excitations were observed, indicating localized character of 5$$f$$ electrons. The excitation energy $$sim$$7 meV of the pseudo doublet state is consistent with the level scheme based on 5$$f^2$$ configuration of U$$^ {4+}$$ ions, which reproduces the magnetic susceptibility, magnetization, and specific heat. With elevating temperature the conductivity recovers with 5$$f$$ carriers excited beyond the gap of 90 K. Simultaneously the CEF excitation becomes weak and broad, and is replaced by a quasi-elastic response of magnetic origin, indicating the crossover of 5$$f$$ character from localized to itinerant.

Journal Articles

Magnetic and nonmagnetic impurity effect on magnetic orderings of the isosceles-triangular-lattice antiferromagnet CuMnO$$_2$$

Terada, Noriki*; Tsuchiya, Yoshinori*; Kitazawa, Hideaki*; Metoki, Naoto

Journal of the Korean Physical Society, 62(12), p.1905 - 1909, 2013/06

 Times Cited Count:2 Percentile:22.1(Physics, Multidisciplinary)

We have investigated magnetic and nonmagnetic impurity substitution effects on magnetic ordering of a frustrated isosceles triangular lattice antiferromagnet CuMnO$$_2$$ by means of the magnetic neutron diffraction measurements on Cu(Mn$$_{1-y}$$Ga$$_y$$)O$$_2$$. While the magnetic wave vector of the magnetic ground state of "magnetically" substituted Cu(Mn$$_{1-x}$$Cu$$_x$$)O$$_2$$ with x = 0:04 is Q = (-1/2 1/2 0), that in the "nonmagnetically" substituted Cu(Mn$$_{1-y}$$Ga$$_y$$)O$$_2$$ with y =0.05, 0.15 and 0.20 is Q = (-1/2 1/2 1/2) that is identical to that of pure CuMnO$$_2$$. We discuss an influence of magnetic or nonmagnetic impurity substitution on the magnetic ordering of CuMnO$$_2$$, by comparing the results of Cu(Mn$$_{1-y}$$Ga$$_y$$)O$$_2$$ with Cu(Mn$$_{1-x}$$Cux)O$$_2$$.

Journal Articles

High-pressure studies of DyB$$_2$$C$$_2$$

Yamauchi, Hiroki; Osakabe, Toyotaka; Kosaka, Masashi*; Matsuoka, Eiichi*; Onodera, Hideya*

Journal of the Korean Physical Society, 62(12), p.2084 - 2087, 2013/06

 Times Cited Count:1 Percentile:12.72(Physics, Multidisciplinary)

Journal Articles

Effects of mechanical rotation and vibration on spin currents

Matsuo, Mamoru; Ieda, Junichi; Maekawa, Sadamichi; Saito, Eiji

Journal of the Korean Physical Society, 62(10), p.1404 - 1409, 2013/05

 Times Cited Count:4 Percentile:36.94(Physics, Multidisciplinary)

In the frontier of spintronics, much attention is paid on the control of spin currents. Due to the recent progress of nanoelectromechanics, mechanical manipulation of spins increases its importance. We discuss theoretically the generation of spin currents in both rotationally and linearly accelerating systems. The spin-orbit interaction argumented by inertial effects is derived from the low energy limit of the generally covariant Dirac equation. It is shown that the spin-orbit interaction is responsible for the generation of spin currents by mechanical rotation and vibration. We also investigate SU(2) $$times$$ U(1) gauge theory in accelerating systems, which allows us to extend the spintronic theory in inertial frame to non-inertial frames.

Oral presentation

Microscopic magnetic hysteresis measurement of amorphous Tb-TM (TM=Fe and Co) thin films by magnetic Compton scattering

Agui, Akane; Unno, Tetsuya*; Matsumoto, Sayaka*; Suzuki, Kosuke*; Sakurai, Hiroshi*

no journal, , 

no abstracts in English

Oral presentation

Growth of highly uniform graphene for spintronic applications

Entani, Shiro; Matsumoto, Yoshihiro; Otomo, Manabu; Avramov, P.; Naramoto, Hiroshi*; Sakai, Seiji

no journal, , 

Oral presentation

Neutron diffraction study of rare-earth compound Ho$$_5$$Pd$$_2$$ with a large magnetocaloric effect

Kitazawa, Hideaki*; Kawamura, Yukihiko*; Terada, Noriki*; Mamiya, Hiroaki*; Suzuki, Hiroyuki*; Doenni, A.*; Kaneko, Koji; Metoki, Naoto; Igawa, Naoki

no journal, , 

We have performed neutron powder diffraction experiments at JRR-3 using polycrystalline Ho$$_5$$Pd$$_2$$. The magnetic peaks with a propagation vector k = (0.18, 0.18, 0.18) are gradually developing below about 100 K. The peak width is significantly broader than an experimental resolution even temperature is 5 K. These results indicate that Ho$$_5$$Pd$$_2$$ is a short-range ordered antiferromagnet with a long wave length.

Oral presentation

Depth-resolved XMCD spectroscopy on single-layer graphene / Ni structure

Matsumoto, Yoshihiro; Entani, Shiro; Otomo, Manabu; Avramov, P.; Naramoto, Hiroshi*; Amemiya, Kenta*; Sakai, Seiji

no journal, , 

Oral presentation

Electronic structure of $$R$$Cu$$_2$$Si$$_2$$ ($$R=$$Yb, Y) studied by soft X-ray angle-resolved photoemission spectroscopy

Yasui, Akira; Fujimori, Shinichi; Kawasaki, Ikuto; Okane, Tetsuo; Takeda, Yukiharu; Saito, Yuji; Yamagami, Hiroshi; Sekiyama, Akira*; Settai, Rikio*; Matsuda, Tatsuma; et al.

no journal, , 

Oral presentation

21 (Records 1-20 displayed on this page)