Refine your search:     
Report No.
 - 
Search Results: Records 1-20 displayed on this page of 90

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

Element-specific insight into ferromagnetic stability in UCoGe revealed by soft X-ray magnetic circular dichroism

Takeda, Yukiharu; Posp$'i$$v{s}$il, J.*; Yamagami, Hiroshi; Yamamoto, Etsuji; Haga, Yoshinori

Physical Review B, 108(8), p.085129_1 - 085129_10, 2023/08

Journal Articles

Enhanced $$d$$-$$p$$ hybridization intertwined with anomalous ground state formation in the van der Waals itinerant magnet Fe$$_5$$GeTe$$_2$$

Yamagami, Kohei*; Fujisawa, Yuita*; Pardo-Almanza, M*; Smith, B. R. M.*; Sumida, Kazuki; Takeda, Yukiharu; Okada, Yoshinori*

Physical Review B, 106(4), p.045137_1 - 045137_8, 2022/07

 Times Cited Count:2 Percentile:37.1(Materials Science, Multidisciplinary)

Journal Articles

Electronic structure of ThPd$$_2$$Al$$_3$$; Impact of the U $$5f$$ states on the electronic structure of UPd$$_2$$Al$$_3$$

Fujimori, Shinichi; Takeda, Yukiharu; Yamagami, Hiroshi; Posp$'i$$v{s}$il, J.*; Yamamoto, Etsuji; Haga, Yoshinori

Physical Review B, 105(11), p.115128_1 - 115128_6, 2022/03

 Times Cited Count:0 Percentile:0(Materials Science, Multidisciplinary)

Journal Articles

Electronic structure of URu$$_2$$Si$$_2$$ in paramagnetic phase; Three-dimensional angle resolved photoelectron spectroscopy study

Fujimori, Shinichi; Takeda, Yukiharu; Yamagami, Hiroshi; Yamamoto, Etsuji; Haga, Yoshinori

Electronic Structure (Internet), 3(2), p.024008_1 - 024008_8, 2021/06

Journal Articles

Manifestation of electron correlation effect in 5$$f$$ states of uranium compounds revealed by 4$$d$$-5$$f$$ resonant photoelectron spectroscopy

Fujimori, Shinichi; Kobata, Masaaki; Takeda, Yukiharu; Okane, Tetsuo; Saito, Yuji; Fujimori, Atsushi; Yamagami, Hiroshi; Haga, Yoshinori; Yamamoto, Etsuji; Onuki, Yoshichika*

Physical Review B, 99(3), p.035109_1 - 035109_5, 2019/01

 Times Cited Count:9 Percentile:53.77(Materials Science, Multidisciplinary)

Journal Articles

Electronic structure of URu$$_2$$Si$$_2$$ studied by photoelectron spectroscopy (INVITED)

Fujimori, Shinichi; Takeda, Yukiharu; Okane, Tetsuo; Saito, Yuji; Fujimori, Atsushi; Yamagami, Hiroshi; Haga, Yoshinori; Yamamoto, Etsuji; Onuki, Yoshichika*

Progress in Nuclear Science and Technology (Internet), 5, p.82 - 85, 2018/11

Journal Articles

Soft X-ray magnetic circular dichroism study on UGe$$_{2}$$

Takeda, Yukiharu; Okane, Tetsuo; Saito, Yuji; Yamagami, Hiroshi; Yamamoto, Etsuji; Haga, Yoshinori

Progress in Nuclear Science and Technology (Internet), 5, p.171 - 174, 2018/11

Journal Articles

Element-specific observation of the ferromagnetic ordering process in UCoAl via soft X-ray magnetic circular dichroism

Takeda, Yukiharu; Saito, Yuji; Okane, Tetsuo; Yamagami, Hiroshi; Matsuda, Tatsuma*; Yamamoto, Etsuji; Haga, Yoshinori; Onuki, Yoshichika*

Physical Review B, 97(18), p.184414_1 - 184414_7, 2018/05

AA2018-0316.pdf:0.62MB

 Times Cited Count:1 Percentile:15.79(Materials Science, Multidisciplinary)

Journal Articles

Electronic structure of ThRu$$_2$$Si$$_2$$ studied by angle-resolved photoelectron spectroscopy; Elucidating the contribution of U 5$$f$$ states in URu$$_{2}$$Si$$_{2}$$

Fujimori, Shinichi; Kobata, Masaaki; Takeda, Yukiharu; Okane, Tetsuo; Saito, Yuji; Fujimori, Atsushi; Yamagami, Hiroshi; Matsumoto, Yuji*; Yamamoto, Etsuji; Tateiwa, Naoyuki; et al.

Physical Review B, 96(12), p.125117_1 - 125117_9, 2017/09

 Times Cited Count:8 Percentile:43.06(Materials Science, Multidisciplinary)

Journal Articles

Electronic structures of U$$X_3$$ ($$X$$=Al, Ga, and In) studied by photoelectron spectroscopy

Fujimori, Shinichi; Kobata, Masaaki; Takeda, Yukiharu; Okane, Tetsuo; Saito, Yuji; Fujimori, Atsushi; Yamagami, Hiroshi; Haga, Yoshinori; Yamamoto, Etsuji; Onuki, Yoshichika*

Physical Review B, 96(11), p.115126_1 - 115126_10, 2017/09

 Times Cited Count:7 Percentile:35.8(Materials Science, Multidisciplinary)

Journal Articles

Electronic structures of uranium compounds studied by soft X-ray photoelectron spectroscopy

Fujimori, Shinichi; Takeda, Yukiharu; Okane, Tetsuo; Saito, Yuji; Fujimori, Atsushi; Yamagami, Hiroshi; Haga, Yoshinori; Yamamoto, Etsuji; Onuki, Yoshichika

Journal of the Physical Society of Japan, 85(6), p.062001_1 - 062001_33, 2016/06

 Times Cited Count:31 Percentile:84.24(Physics, Multidisciplinary)

Journal Articles

Recent progress of soft X-ray photoelectron spectroscopy studies of uranium compounds

Fujimori, Shinichi; Takeda, Yukiharu; Okane, Tetsuo; Saito, Yuji; Fujimori, Atsushi; Yamagami, Hiroshi; Yamamoto, Etsuji; Haga, Yoshinori; Onuki, Yoshichika

Journal of Electron Spectroscopy and Related Phenomena, 208, p.105 - 110, 2016/04

 Times Cited Count:1 Percentile:8.62(Spectroscopy)

Recent progresses in the soft X-ray photoelectron spectroscopy (PES) studies ($$h nu$$ $$_sim^{>}$$ 100 eV) for uranium compounds are briefly reviewed. The soft X-ray PES has enhanced sensitivities for the bulk U 5f electronic structure, which is essential to understand the unique physical properties of uranium compounds. In particular, the recent remarkable improvement in energy resolutions from an order of 1 eV to 100 meV made it possible to observe fine structures in Uf density of states. Furthermore, soft X-ray ARPES becomes available due to the increase of photon flux at beamlines in third generation synchrotron radiation facilities. The technique made it possible to observe bulk band structures and Fermi surfaces of uranium compounds and therefore, the results can be directly compared with theoretical models such as band-structure calculations. The core-level spectra of uranium compounds show a systematic behavior depending on their electronic structures, suggesting that they can be utilized to determine basic physical parameters such as the U 5f-ligand hybridizations or Coulomb interaction between U 5f electrons. It is shown that soft X-ray PES provides unique opportunities to understand the electronic structures of uranium compounds.

Journal Articles

Characteristic fermi surface properties of V$$_2$$Ga$$_5$$, CoGa$$_3$$, TiGa$$_3$$, ZrGa$$_3$$, and ZrAl$$_3$$ with different tetragonal structures

Teruya, Atsushi*; Takeda, Masataka*; Nakamura, Ai*; Harima, Hisatomo*; Haga, Yoshinori; Uchima, Kiyoharu*; Hedo, Masato*; Nakama, Takao*; Onuki, Yoshichika*

Journal of the Physical Society of Japan, 84(5), p.054703_1 - 054703_15, 2015/05

 Times Cited Count:4 Percentile:35.01(Physics, Multidisciplinary)

Journal Articles

Electronic structures of ferromagnetic superconductors UGe$$_{2}$$ and UCoGe studied by angle-resolved photoelectron spectroscopy

Fujimori, Shinichi; Okochi, Takuo*; Kawasaki, Ikuto*; Yasui, Akira*; Takeda, Yukiharu; Okane, Tetsuo; Saito, Yuji; Fujimori, Atsushi; Yamagami, Hiroshi; Haga, Yoshinori; et al.

Physical Review B, 91(17), p.174503_1 - 174503_9, 2015/05

 Times Cited Count:23 Percentile:70.81(Materials Science, Multidisciplinary)

The electronic structures of the ferromagnetic superconductors UGe$$_2$$ and UCoGe in the paramagnetic phase were studied by angle-resolved photoelectron spectroscopy using soft X-rays ($$h nu$$ = 400-500 eV). The quasi-particle bands with large contributions from U 5$$f$$ states were observed in the vicinity of EF, suggesting that the U 5$$f$$ electrons of these compounds have an itinerant character. Their overall band structures were explained by the band-structure calculations treating all the U 5$$f$$ electrons as being itinerant. Meanwhile, the states in the vicinity of EF show considerable deviations from the results of band-structure calculations, suggesting that the shapes of Fermi surface of these compounds are qualitatively different from the calculations, possibly caused by electron correlation effect in the complicated band structures of the low-symmetry crystals. Strong hybridization between U 5$$f$$ and $$mathrm{Co} 3d$$ states in UCoGe were found by the $$mathrm{Co}$$ 2p-3d resonant photoemission experiment, suggesting that $$mathrm{Co} 3d$$ states have finite contributions to the magnetic, transport, and superconducting properties.

JAEA Reports

Study on engineering technologies in the Mizunami Underground Research Laboratory (FY 2013); Development of recovery and mitigation technology on excavation damage (Contract research)

Fukaya, Masaaki*; Hata, Koji*; Akiyoshi, Kenji*; Sato, Shin*; Takeda, Yoshinori*; Miura, Norihiko*; Uyama, Masao*; Kaneda, Tsutomu*; Ueda, Tadashi*; Toda, Akiko*; et al.

JAEA-Technology 2014-040, 199 Pages, 2015/03

JAEA-Technology-2014-040.pdf:37.2MB

The researches on engineering technology in the Mizunami Underground Research Laboratory (MIU) project consists of (1) development of design and construction planning technologies, (2) development of construction technology, (3) development of countermeasure technology, (4) development of technology for security, and (5) development of technologies for restoration and/or reduction of the excavation damage. The researches on engineering technology such as verification of the initial design were being conducted by using data measured during construction as a part of the second phase of the MIU plan. Examination about the plug for reflood test in the GL-500m Access/Research Gallery-North as part of the development of technologies for restoration and/or reduction of excavation damage were carried out. Specifically, Literature survey was carried out about the plug, based on the result of literature survey, examination of the design condition, design of the plug and rock stability using numerical simulation, selection of materials for major parts, and grouting for water inflow from between rock and plug, were carried out in this study.

JAEA Reports

Study on engineering technologies in the Mizunami Underground Research Laboratory; FY2012 (Contract research)

Fukaya, Masaaki*; Noda, Masaru*; Hata, Koji*; Takeda, Yoshinori*; Akiyoshi, Kenji*; Ishizeki, Yoshikazu*; Kaneda, Tsutomu*; Sato, Shin*; Shibata, Chihoko*; Ueda, Tadashi*; et al.

JAEA-Technology 2014-019, 495 Pages, 2014/08

JAEA-Technology-2014-019.pdf:82.23MB

The researches on engineering technology in the Mizunami Underground Research Laboratory (MIU) plan consists of (1) research on engineering technology deep underground, and (2) research on engineering technology as a basis of geological disposal. The former research is mainly aimed in this study, which is categorized in (a) development of design and construction planning technologies, (b) development of construction technologies, (c) development of countermeasure technologies, and (d) development of technologies for security. In this study, the researches on engineering technology are being conducted in these four categories by using data measured during construction as a part of the second phase of the MIU plan.

Journal Articles

Angle resolved photoelectron spectroscopy study of heavy fermion superconductor UPd$$_{2}$$Al$$_{3}$$

Fujimori, Shinichi; Kawasaki, Ikuto*; Yasui, Akira*; Takeda, Yukiharu; Okane, Tetsuo; Saito, Yuji; Fujimori, Atsushi; Yamagami, Hiroshi; Haga, Yoshinori; Yamamoto, Etsuji; et al.

JPS Conference Proceedings (Internet), 3, p.011072_1 - 011072_5, 2014/06

In this presentation, we review some of our recent photoemission studies on uranium superconductors by means of soft X-ray synchrotron radiation ARPES (SX-ARPES). Results of SX-ARPES study on URhGe and UPd$$_{2}$$Al$$_{3}$$ will be presented. URhGe is a ferromagnetic superconductor with $$T_{rm Curie}$$ = 9.5 K and $$T_{rm SC}$$ = 0.26 K while UPd$$_{2}$$Al$$_{3}$$ is an antiferromagnetic superconductor with $$T_{rm N}$$ = 14 K and $$T_{rm SC}$$ = 1.8 K. We have revealed the three-dimensional electronic structures of those compounds by SX-ARPES, and they are compared with those calculated by LDA.

Journal Articles

Itinerant magnetism in URhGe revealed by angle-resolved photoelectron spectroscopy

Fujimori, Shinichi; Kawasaki, Ikuto*; Yasui, Akira*; Takeda, Yukiharu; Okane, Tetsuo; Saito, Yuji; Fujimori, Atsushi*; Yamagami, Hiroshi; Haga, Yoshinori; Yamamoto, Etsuji; et al.

Physical Review B, 89(10), p.104518_1 - 104518_7, 2014/03

 Times Cited Count:21 Percentile:65.37(Materials Science, Multidisciplinary)

The electronic structure of the ferromagnetic superconductor URhGe in the paramagnetic phase has been studied by angle-resolved photoelectron spectroscopy using soft X rays ($$hnu$$ = 595-700 eV). Dispersive bands with large contributions from U 5$$f$$ states were observed in the ARPES spectra, and form Fermi surfaces. The band structure in the paramagnetic phase is partly explained by the band-structure calculation treating all U 5$$f$$ electrons as being itinerant, suggesting that an itinerant description of U 5$$f$$ states is a good starting point for this compound. On the other hand, there are qualitative disagreements especially in the band structure near the Fermi level ($$E$$$$_{rm B}$$ $$_sim^{<}$$ 0.5 eV). The experimentally observed bands are less dispersive than the calculation, and the shape of the Fermi surface is different from the calculation. The changes in spectral functions due to the ferromagnetic transition were observed in bands near the Fermi level, suggesting that the ferromagnetism in this compound has an itinerant origin.

Journal Articles

Separation of magnetic properties at uranium and cobalt sites in UCoAl using soft X-ray magnetic circular dichroism

Takeda, Yukiharu; Saito, Yuji; Okane, Tetsuo; Yamagami, Hiroshi; Matsuda, Tatsuma*; Yamamoto, Etsuji; Haga, Yoshinori; Onuki, Yoshichika; Fisk, Z.

Physical Review B, 88(7), p.075108_1 - 075108_6, 2013/08

 Times Cited Count:9 Percentile:43.58(Materials Science, Multidisciplinary)

no abstracts in English

Journal Articles

Observation of bulk band dispersions of YbRh$$_2$$Si$$_2$$ using soft X-ray angle-resolved photoemission spectroscopy

Yasui, Akira*; Saito, Yuji; Fujimori, Shinichi; Kawasaki, Ikuto*; Okane, Tetsuo; Takeda, Yukiharu; Lapertot, G.*; Knebel, G.*; Matsuda, Tatsuma*; Haga, Yoshinori; et al.

Physical Review B, 87(7), p.075131_1 - 075131_6, 2013/02

 Times Cited Count:6 Percentile:29.47(Materials Science, Multidisciplinary)

We have performed soft X-ray angle-resolved photoemission spectroscopy (ARPES) measurements on YbRh$$_2$$Si$$_2$$ and clarified its three-dimensional bulk valence-band structures. The ARPES spectra have not only Yb$$^{3+}$$ multiplet peaks but also a finite contribution of Yb$$^{2+}$$ peaks at 15 K, corresponding to the valence fluctuating behavior in this compound. This means that Yb 4f electrons in this compound have itinerant character below the $$T_{rm K}$$. We have found that dispersions of the valence bands except the vicinity of the Yb 4f bands agree better with those of the band-structure calculation of LuRh$$_2$$Si$$_2$$ than those of YbRh$$_2$$Si$$_2$$ within a local-density approximation. In addition, the Yb 3d-4f resonant photoemission spectra of YbRh$$_2$$Si$$_2$$ strongly suggest the existence of Yb 5d electrons in the valence band. We conclude that the charge transfer from the Yb 4f state to the Yb 5d state has an important role in the formation of the valence band of YbRh$$_2$$Si$$_2$$.

90 (Records 1-20 displayed on this page)