JAEA
  • help
  • PC | SP
  • JP | EN
          
Refine your search：     
Report No.
 - 
Clear All
Search Results: Records 1-20 displayed on this page of 38

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

Dramatic elastic response at the critical end point in UTe$$_2$$

Vali$v{s}$ka, M.*; Haidamak, T.*; Cabala, A.*; Posp$'i$$v{s}$il, J.*; Bastien, G.*; Sechovsk$'y$, V.*; Prokle$v{s}$ka, J.*; Yanagisawa, Tatsuya*; Opletal, P.; Sakai, Hironori; et al.

Physical Review Materials (Internet), 8(9), p.094415_1 - 094415_9, 2024/09

https://doi.org/10.1103/PhysRevMaterials.8.094415
 Times Cited Count：0 Percentile：0.00(Materials Science, Multidisciplinary)

Journal Articles

Precise magnetization measurements down to 500 mK using a miniature $$^3$$He cryostat and a closed-cycle $$^3$$He gas handling system installed in a SQUID magnetometer without continuous-cooling functionality

Shimamura, Kazutoshi*; Wajima, Hiroki*; Makino, Hayato*; Abe, Satoshi*; Haga, Yoshinori; Sato, Yoshiaki*; Kawae, Tatsuya*; Yoshida, Yasuo*

Japanese Journal of Applied Physics, 61(5), p.056502_1 - 056502_7, 2022/05

https://doi.org/10.35848/1347-4065/ac5bb0
 Times Cited Count：1 Percentile：8.10(Physics, Applied)

Journal Articles

Magnetic anisotropy and thermodynamic anomaly in the superconducting mixed state of UBe$$_{13}$$ probed by static dc magnetization measurements

Shimizu, Yusei*; Haga, Yoshinori; Yanagisawa, Tatsuya*; Amitsuka, Hiroshi*

Physical Review B, 93(2), p.024502_1 - 024502_8, 2016/01

https://doi.org/10.1103/PhysRevB.93.024502
 Times Cited Count：8 Percentile：35.32(Materials Science, Multidisciplinary)

Journal Articles

DC magnetization study on heavy-electron superconductor UBe$$_{13}$$

Shimizu, Yusei*; Haga, Yoshinori; Yanagisawa, Tatsuya*; Amitsuka, Hiroshi*; Aoki, Dai*; Brison, J.-P.*; Braithwaite, D.*

JPS Conference Proceedings (Internet), 3, p.015009_1 - 015009_6, 2014/06

https://doi.org/10.7566/JPSCP.3.015009

Journal Articles

Observation of an unusual magnetic anomaly in the superconducting mixed state of heavy-fermion compound UBe$$_{13}$$ by precise dc magnetization measurements

Shimizu, Yusei*; Haga, Yoshinori; Ikeda, Yoichi*; Yanagisawa, Tatsuya*; Amitsuka, Hiroshi*

Physical Review Letters, 109(21), p.217001_1 - 217001_5, 2012/11

https://doi.org/10.1103/PhysRevLett.109.217001
 Times Cited Count：18 Percentile：67.56(Physics, Multidisciplinary)

Journal Articles

Maki parameter and upper critical field of the heavy-fermion superconductor UBe$$_{13}$$

Shimizu, Yusei*; Ikeda, Yoichi*; Wakabayashi, Takumi*; Haga, Yoshinori; Tenya, Kenichi*; Hidaka, Hiroyuki*; Yanagisawa, Tatsuya*; Amitsuka, Hiroshi*

Journal of the Physical Society of Japan, 80(9), p.093701_1 - 093701_4, 2011/09

https://doi.org/10.1143/JPSJ.80.093701
 Times Cited Count：8 Percentile：49.74(Physics, Multidisciplinary)

Journal Articles

Specific heat and magnetization studies of the superconducting mixed state of UBe$$_{13}$$

Shimizu, Yusei*; Ikeda, Yoichi*; Wakabayashi, Takumi*; Tenya, Kenichi*; Haga, Yoshinori; Hidaka, Hiroyuki*; Yanagisawa, Tatsuya*; Amitsuka, Hiroshi*

Journal of the Physical Society of Japan, 80(Suppl.A), p.SA100_1 - SA100_3, 2011/07

https://doi.org/10.1143/JPSJS.80SA.SA100
 Times Cited Count：1 Percentile：11.01(Physics, Multidisciplinary)

Journal Articles

Ultrasonic measurements on the cage-structured clathrate compound U$$_3$$Pd$$_{20}$$Si$$_6$$

Yanagisawa, Tatsuya*; Tateiwa, Naoyuki; Mayama, Taichi*; Saito, Hitoshi*; Hidaka, Hiroyuki*; Amitsuka, Hiroshi*; Haga, Yoshinori; Nemoto, Yuichi*; Goto, Terutaka*

Journal of the Physical Society of Japan, 80(Suppl.A), p.SA105_1 - SA105_3, 2011/07

https://doi.org/10.1143/JPSJS.80SA.SA105
 Times Cited Count：3 Percentile：26.78(Physics, Multidisciplinary)

Journal Articles

Magnetization in the superconducting mixed state of the heavy-fermion compound UBe$$_{13}$$

Shimizu, Yusei*; Ikeda, Yoichi*; Wakabayashi, Takumi*; Tenya, Kenichi*; Haga, Yoshinori; Hidaka, Hiroyuki*; Yanagisawa, Tatsuya*; Amitsuka, Hiroshi*

Journal of Physics; Conference Series, 273, p.012084_1 - 012084_4, 2011/02

https://doi.org/10.1088/1742-6596/273/1/012084
 Times Cited Count：3 Percentile：61.86(Physics, Condensed Matter)

Journal Articles

Ga NQR relaxation rates in superconductor PuRhGa$$_5$$

Sakai, Hironori; Kambe, Shinsaku; Tokunaga, Yo; Fujimoto, Tatsuya; Walstedt, R. E.*; Yasuoka, Hiroshi; Aoki, Dai*; Homma, Yoshiya*; Yamamoto, Etsuji; Nakamura, Akio; et al.

Journal of Physics and Chemistry of Solids, 68(11), p.2103 - 2106, 2007/11

https://doi.org/10.1016/j.jpcs.2007.08.039
 Times Cited Count：1 Percentile：7.31(Chemistry, Multidisciplinary)

A lot of attention is currently focused on Pu-based superconductors. These systems have relatively high superconducting (SC) transition temperatures, ${it i.e.,}$ $$T_{rm c}simeq$$ 18 K for PuCoGa$$_{5}$$ and $$T_{rm c}simeq$$ 9 K for PuRhGa$$_{5}$$. Both compounds crystallize in the tetragonal HoCoGa$$_{5}$$ (115) structure, which is well known for the heavy-fermion SC systems Ce$$T$$In$$_{5}$$ ($$T$$=Co, Rh, Ir)with $$T_{rm c} sim$$ 2 K at most. Recently, NMR and NQR experiments have been reported for PuCoGa$$_{5}$$ by Curro et al. and for PuRhGa$$_{5}$$ by our group. In both cases, measurements of $$1/T_{1}$$ using NQR have revealed that the Pu115 superconductors show unconventional superconductivity with an anisotropic gap. Now we have measured the more detailed data of $$1/T_{1}$$ for NQR lines in PuRhGa$$_5$$, especially focusing on the low-lying magnetic excitation in the normal state. From the viewpoint of spin-fluctuations, we will discuss the difference between PuRhGa$$_{5}$$ and PuCoGa$$_{5}$$ and between superconducting Pu115 and non-superconducting An115 series.

Journal Articles

NMR studies of actinide dioxides

Tokunaga, Yo; Sakai, Hironori; Fujimoto, Tatsuya; Kambe, Shinsaku; Walstedt, R. E.*; Ikushima, Kenji*; Yasuoka, Hiroshi; Aoki, Dai*; Homma, Yoshiya*; Haga, Yoshinori; et al.

Journal of Alloys and Compounds, 444-445, p.241 - 245, 2007/10

https://doi.org/10.1016/j.jallcom.2007.03.082
 Times Cited Count：22 Percentile：70.10(Chemistry, Physical)

In this paper, we present our recent NMR works on Neptunium and Plutonium compounds. In order to elucidate the nature of the exotic multipolar ordered phase of NpO$$_2$$, we have initiated the first NMR measurements on this system. We have shown that direct observation of multipole order parameters is possible by means of NMR. Our NMR results provide further insight into the microscopic nature of multipole phase transitions in f-electron systems. We have also performed $$^{69,71}$$Ga NMR/NQR studies on a single crystal of PuRhGa$$_5$$. From the temperature dependence of the spin-lattice relaxation rate ($$1/T_1$$), we have found that PuRhGa$$_5$$ is an unconventional superconductor having an anisotropic superconducting (SC) gap 2$$Delta(0)$$=5$$K_BT_c$$. Furthermore, we have confirmed the Knight shift to be decreased below $$T_c$$. This gives strong evidence for spin singlet SC pairing.

Journal Articles

NMR study of the semimetallic compound UCoGa$$_5$$

Kambe, Shinsaku; Sakai, Hironori; Kato, Harukazu*; Tokunaga, Yo; Fujimoto, Tatsuya*; Walstedt, R. E.*; Ikeda, Shugo; Maehira, Takahiro*; Haga, Yoshinori; Onuki, Yoshichika

Physical Review B, 76(2), p.024411_1 - 024411_6, 2007/07

https://doi.org/10.1103/PhysRevB.76.024411
 Times Cited Count：6 Percentile：30.41(Materials Science, Multidisciplinary)

We report NMR studies on a single crystal of UCoGa$$_5$$, which has the same tetragonal HoCoGa$$_5$$ (115) structure as the$$d$$-wave high-$$T_c$$ superconductor PuCoGa$$_5$$. The spin-lattice relaxation rate ($$1/T_1$$) in UCoGa$$_5$$ issmall comparing with those of other actinide 115 compounds. This fact is consistent with a semi-metallic nature of UCoGa$$_5$$ suggested by de Haas-van Alphen effect measurements and band calculations. From comparison of $$1/T_1$$ at crystallografically different Ga and Co sites and the static susceptibility, an existence of two bands with rather different characters is revealed.

Journal Articles

Favorable magnetic fluctuation anisotropy for unconventional superconductivity in $$f$$-electron systems

Kambe, Shinsaku; Sakai, Hironori; Tokunaga, Yo; Fujimoto, Tatsuya*; Walstedt, R. E.*; Ikeda, Shugo; Aoki, Dai*; Homma, Yoshiya*; Haga, Yoshinori; Shiokawa, Yoshinobu*; et al.

Physical Review B, 75(14), p.140509_1 - 140509_4, 2007/04

https://doi.org/10.1103/PhysRevB.75.140509
 Times Cited Count：19 Percentile：61.25(Materials Science, Multidisciplinary)

We report spin-lattice relaxation time measurements in isostructural (HoCoGa$$_5$$ type) actinide compounds withdifferent ground states (paramagnet, antiferromagnet and superconductor) using single-crystal samples. The anisotropy oflocal magnetic fluctuation due to ${it LS}$ coupling on the actinide (magnetic) site is evaluated. In the superconductor PuRhGa$$_5$$, the ${it XY}$ type magnetic anisotropy is strong compared with non-superconducting compounds. Favorable magnetic anisotropy for $$d$$-wave superconductivity in $$f$$-electron systems is discussed.

Journal Articles

NMR/NQR study of the quadrupole orders in binary uranium-palladium intermetallic compound

Fujimoto, Tatsuya; Haga, Yoshinori; Sakai, Hironori; Tokunaga, Yo; Kambe, Shinsaku; Onuki, Yoshichika*

Journal of Magnetism and Magnetic Materials, 310(2, Part1), p.746 - 747, 2007/03

UPd$$_3$$ shows the successive quadrupole orders at $$T_{rm Q0}=7.5$$ K, $$T_{rm Q1}=6.8$$ K and $$T_{rm Q2}=4.5$$ K. The phase transition at $$T_{rm Q0}$$ comes from the (1/2,0,1/2)-type quadrupole orders on quasi-cubic uranium-sublattice. On the other hand, the quadrupole states below $$T_{rm Q1}$$ are still controversial; while the Polarized Neutron Diffraction suggested the triple-$$q$$ structure, the Resonant X-ray Scattering assumed the canted quadrupole order. In addition, below $$T_{rm Q2}$$, an antiferromagnetic order has been suggested, but the magnetic structure and so on are not still identified. To investigate the local symmetry of the quadruple order in UPd$$_3$$, we tried the nuclear quadrupole resonance, and we succeeded to find the first spin-echo signals from the UPd$$_3$$ probed by $$^{105}$$Pd nuclei. In this paper, we report the nuclear properties of $$^{105}$$Pd isotope and discuss the characteristics of the quadrupole orders emerging in each temperature phases.

Journal Articles

NMR study of magnetic fluctuations in 115 actinide compounds

Kambe, Shinsaku; Sakai, Hironori; Tokunaga, Yo; Kato, Harukazu; Fujimoto, Tatsuya; Walstedt, R. E.*; Ikeda, Shugo; Matsuda, Tatsuma; Haga, Yoshinori; Aoki, Dai*; et al.

Journal of Magnetism and Magnetic Materials, 310(2, Part1), p.176 - 181, 2007/03

performed NMR measurements in 5f-115 compounds with various ground states [UFeGa$$_{5}$$ (Paramagnet), UPtGa$$_{5}$$, NpCoGa$$_{5}$$, NpFeGa$$_{5}$$ (Antiferromagnet) and PuRhGa$$_{5}$$ (Superconductor)], and evaluated the T-dependence of the local (actinide site) magnetic fluctuation energies (//c and c) in the paramagnetic states. An anisotropy in the magnetic fluctuations is observed in all compounds due to the strong LS coupling, in contrast to 3d-high Tc cuprates which have isotropic magnetic fluctuations at Cu sites. It is remarkable that the XY-type magnetic anisotropy is strong in PuRhGa$$_{5}$$ comparing with the non-superconducting 5f-115 compounds. The fluctuation energy in PuRhGa$$_{5}$$ is of the order of 10meV which is between of heavy fermion superconductors (1meV for $$T$$$$_{rm c}$$1K) and high $$T$$$$_{rm c}$$ cuprates (102meV for $$T$$$$_{rm c}$$100K). The relation between the magnetic fluctuation properties and the ground states will be discussed.

Journal Articles

Enhancement of relaxation rates in the normal state of superconductor PuRhGa$$_5$$:NQR relaxation study

Sakai, Hironori; Kambe, Shinsaku; Tokunaga, Yo; Fujimoto, Tatsuya; Walstedt, R. E.*; Yasuoka, Hiroshi; Aoki, Dai*; Homma, Yoshiya*; Yamamoto, Etsuji; Nakamura, Akio; et al.

Journal of Magnetism and Magnetic Materials, 310(2, Part1), p.e118 - e119, 2007/03

The spin-lattice relaxation rates ($$1/T_1$$) have been measured under zero fieldusing nuclear quadrupole resonance (NQR) linesin superconductor PuRhGa$$_5$$ and Pauli-paramagnet LuCoGa$$_5$$. In the reference LuCoGa$$_5$$ with fully-occupied $$4f$$ shell, the $$1/T_1$$ shows the constant behavior of $$(T_1T)^{-1}=0.495pm0.002$$ (sec$$cdot$$K)$$^{-1}$$. On the other hand, in PuRhGa$$_5$$, $$1/T_1$$ is much larger than in LuCoGa$$_5$$and the $$1/T_1propto T$$ behavior below $$sim$$30 K is seen, where its $$(T_{1}T)^{-1}$$ value is 3.27 $$pm$$ 0.005 (sec$$cdot$$K)$$^{-1}$$. These results suggest a development of coherent Fermi liquid stateincorporated with $$5f$$ electronsbelow $$sim$$30 K in PuRhGa$$_5$$.

Journal Articles

NMR shift measurements of $$^{69}$$Ga in unconventional superconductor PuRhGa$$_{5}$$

Sakai, Hironori; Tokunaga, Yo; Fujimoto, Tatsuya; Kambe, Shinsaku; Walstedt, R. E.; Yasuoka, Hiroshi; Aoki, Dai*; Homma, Yoshiya*; Yamamoto, Etsuji; Nakamura, Akio; et al.

Journal of the Physical Society of Japan, 75(Suppl.), p.50 - 52, 2006/08

Very recently, we have succeeded in NMR/NQR measurements for PuRhGa$$_{5}$$. PuRhGa$$_{5}$$ is a superconductor with $$T_{c}$$$$approx$$9 K, which is isomorphic to PuCoGa$$_{5}$$ with the higher $$T_{c}$$=18 K. We have reported that PuRhGa$$_{5}$$ is an unconventional superconductor with an anisotropic gap, through the measurement of NQR spin-lattice relaxation rate $$1/T_{1}$$ , while PuCoGa$$_{5}$$ is also reported to be such an anisotropic superconductor. The Knight shift $$K$$ and $$1/T_{1}$$ of NMR under applied field for the normal state of PuRhGa$$_{5}$$ suggest an anisotropic feature of hyperfine and/or spin fluctuation in this system. We will outline the superconducting state and report the nature of the normal state based on the basis of $$K$$ and $$1/T_{1} T$$ results. The difference between PuRhGa$$_{5}$$ and PuCoGa$$_{5}$$ will be also discussed.

Journal Articles

Observation of ferromagnetic and antiferromagnetic correlations in UIr$$_{3}$$B$$_{2}$$

Fujimoto, Tatsuya; Sakai, Hironori; Tokunaga, Yo; Kambe, Shinsaku; Walstedt, R. E.; Ikeda, Shugo; Matsuda, Tatsuma; Haga, Yoshinori; Onuki, Yoshichika

Journal of the Physical Society of Japan, 75(Suppl.), p.113 - 115, 2006/08

The low-dimensional systems exhibit wide-variety of physical properties. In the antiferromagnetic triangular lattice, for instance, resonating valence bond state is expected, furthermore, in one-dimensional (1D) systems, metal-insulator transition (Peierls transition) occurs due to charge-lattice couplings. Up to now, the study of low-dimensional systems has been mostly performed in oxides and organic compounds, but it is rare in the rare-earth and actinide intermetallics. To looking for the novel low-dimensionality in $$f$$-electron systems, we focused on the UIr$$_3$$B$$_2$$, and NMR measurement was carried out. From Knight shift and nuclear spin-lattice relaxation rates, ferromagnetic correlations develop above 50 K, but below 50 K, the emergence of antiferromagnetic correlations was clarified along with the saturation of ferromagnetic correlations. The possible model to explain the obtained result is nesting effect on the 1D Fermi surface, and it is expected that UIr$$_3$$B$$_2$$ will be the typical compound to investigate the physical properties of 1D $$f$$-electrons systems.

Journal Articles

NMR study of antiferromagnet UPtGa$$_{5}$$

Kambe, Shinsaku; Sakai, Hironori; Tokunaga, Yo; Fujimoto, Tatsuya; Kato, Harukazu; Walstedt, R. E.; Ikeda, Shugo; Matsuda, Tatsuma; Haga, Yoshinori; Onuki, Yoshichika

Journal of the Physical Society of Japan, 75(Suppl.), p.127 - 129, 2006/08

Recently, new superconductors have been discovered in Pu-based HoCoGa$$_5$$(115) structure compounds: PuCoGa$$_5$$ ($$T_{c}=18K$$) and PuRhGa$$_5$$ ($$T_{c}=9K$$). The discovery has stimulated a lot of interest in actinide compounds. We report NMR measurements on a high-quality single crystal sample of the non-superconducting U- and Np-based 115 compounds. In order to elucidate universal magnetic properties and the origin of superconductivity in the 115 families, spin-lattice relaxation and Knight shift measurements have been performed systematically in the non-superconducting 115 compounds. Comparison of dynamical properties with the superconducting Pu115 compounds will be presented.

Journal Articles

Anomalous magnetic correlations in heavy fermion Pauli paramagnet UIr$$_3$$B$$_2$$; $$^{11}$$B NMR study

Fujimoto, Tatsuya; Sakai, Hironori; Tokunaga, Yo; Kambe, Shinsaku; Walstedt, R. E.; Ikeda, Shugo; Matsuda, Tatsuma; Haga, Yoshinori; Onuki, Yoshichika

Physica B; Condensed Matter, 378-380, p.997 - 998, 2006/05

https://doi.org/10.1016/j.physb.2006.01.382
 Times Cited Count：0 Percentile：0.00(Physics, Condensed Matter)

We report $$^{11}$$B NMR results of a single crystal UIr$$_3$$B$$_2$$. The measurement was performed by Fast Fourier Transformation technique, because spectral line width is extremely narrow ($$simeq$$ 10 kHz) and NMR occurs in quite limited r.f. band due to a good sample quality. From temperature variation of Knight shift and nuclear spin-lattice relaxation rate, the development of ferromagnetic correlations was clarified in the temperature range above $$T^{*} simeq 50$$ K. On the other hand, the magnetic dynamics was changed into another novel state below $$T^{*}$$; ferromagnetic correlations are restrained, meanwhile antiferromagnetic correlations are newly emerged. To explain this characteristic ground state, the one-dimensional $$5f$$ electrons state due to the unique structural lattice of UIr$$_3$$B$$_2$$ was proposed.

38 (Records 1-20 displayed on this page)