Local structure of functional solids

Shamoto, Shinichi

Journal of the Physical Society of Japan, 88(8), p.081008_1 - 081008_11, 2019/08

https://doi.org/10.7566/JPSJ.88.081008

Te-NMR study on a single crystal of heavy fermion superconductor UTe

Tokunaga, Yo; Sakai, Hironori; Kambe, Shinsaku; Hattori, Taisuke; Higa, Nonoka; Nakamine, Genki*; Kitagawa, Shunsaku*; Ishida, Kenji*; Nakamura, Ai*; Shimizu, Yusei*; et al.

Journal of the Physical Society of Japan, 88(7), p.073701_1 - 073701_4, 2019/07

https://doi.org/10.7566/JPSJ.88.073701

We report Te-NMR studies on a newly discovered heavy fermion superconductor UTe. Using a single crystal, we have measured the Te-NMR Knight shift and spin-lattice relaxation rate for fields along the three orthorhombic crystal axes. The data confirm a moderate Ising anisotropy for both the static () and dynamical susceptibilities () in the paramagnetic state above about 20 K. Around 20 K, however, we have observed a sudden loss of NMR spin-echo signal due to sudden enhancement of the NMR spin-spin relaxation rate , when the field is applied along the easy axis of magnetization (= axis). This behavior suggests the development of longitudinal magnetic fluctuations along the axis at very low frequencies below 20 K.

Evidence for weak spin-orbit interaction experienced by Cooper pairs in the spin-triplet superconductor UPt; Pt-NMR study

Aoyama, Taisuke*; Kotegawa, Hisashi*; Kimura, Noriaki*; Yamamoto, Etsuji; Haga, Yoshinori; Onuki, Yoshichika*; To, Hideki*

Journal of the Physical Society of Japan, 88(6), p.064706_1 - 064706_7, 2019/06

https://doi.org/10.7566/JPSJ.88.064706

Electronic structure in heavy fermion compound UPdAl through directional Compton profile measurement

Koizumi, Akihisa*; Kubo, Yasunori*; Yamamoto, Etsuji; Haga, Yoshinori; Sakurai, Yoshiharu*

Journal of the Physical Society of Japan, 88(3), p.034714_1 - 034714_6, 2019/03

https://doi.org/10.7566/JPSJ.88.034714

Localized 5 states in UPdAl and valence crossover in the Vicinity of Heavy-Fermion superconductivity

Metoki, Naoto; Haga, Yoshinori; Yamamoto, Etsuji; Matsuda, Masaaki*

Journal of the Physical Society of Japan, 87(11), p.114712_1 - 114712_9, 2018/11

https://doi.org/10.7566/JPSJ.87.114712

The localized 5 states with 5 () configuration of U ion have been revealed in UPdAl. We found that the low-lying states are the same as PrPdAl flat orbitals with large are stabilized by a two-dimensional CEF potential in the unique crystal structure. The present study involves the valence crossover from tetravalent to trivalent in a series of AnPdAl, demonstrated by lattice and/or transport anomaly as well as many body effects in the vicinity of the boundary. The valence instability plays important role for the unusual heavy fermion superconductivity in NpPdAl.

Imaging measurement of neutron attenuation by small-angle neutron scattering using soller collimator

Oba, Yojiro; Shinohara, Takenao; Sato, Hirotaka*; Onodera, Yohei*; Hiroi, Kosuke; Su, Y.; Sugiyama, Masaaki*

Journal of the Physical Society of Japan, 87(9), p.094004_1 - 094004_5, 2018/09

https://doi.org/10.7566/JPSJ.87.094004

no abstracts in English

On the ordered states in a two-dimensional Heisenberg model with dipole-dipole interactions

Yokota, Terufumi

Journal of the Physical Society of Japan, 87(9), p.094701_1 - 094701_5, 2018/09

https://doi.org/10.7566/JPSJ.87.094701

Neutron inelastic scattering study of the -electron states in NdPdAl

Metoki, Naoto; Yamauchi, Hiroki; Suzuki, Hiroyuki*; Kitazawa, Hideaki*; Kamazawa, Kazuya*; Ikeuchi, Kazuhiko*; Kajimoto, Ryoichi; Nakamura, Mitsutaka; Inamura, Yasuhiro

Journal of the Physical Society of Japan, 87(8), p.084708_1 - 084708_7, 2018/08

https://doi.org/10.7566/JPSJ.87.084708

Inelastic neutron scattering experiments were carried out in order to study the -electron states of NdPdAlThe CEF levels at 0K, 35.4K, 88.3K, 101.5K, and 198.8K were clarified from the excitation spectra. The ground state contains the orbital with as a main component due to a large negative BK, which is the origin of the strong uniaxial anisotropy. The estimated magnetic moment, the calculated susceptibility, magnetization curve, and specific heat are in good agreement with the experimental data. The existence of a common charge distribution with CePdAl and PrPdAl. Indicates that a localized character is important even in actinide-based iso-structural compounds as actually observed in UPdAl and also NpPdAl, in which the valence crossover plays important role for the heavy fermion superconductivity.

Anisotropic superconductivity emerging from the orbital degrees of freedom in a non-Kramers doublet system

Kubo, Katsunori

Journal of the Physical Society of Japan, 87(7), p.073701_1 - 073701_4, 2018/07

https://doi.org/10.7566/JPSJ.87.073701

Continuum excitation and pseudospin wave in quantum spin-liquid and quadrupole ordered states of TbTiO

Kadowaki, Hiroaki*; Wakita, Mika*; Fk, B.*; Ollivier, J.*; Kawamura, Seiko; Nakajima, Kenji; Takatsu, Hiroshi*; Tamai, Mototake*

Journal of the Physical Society of Japan, 87(6), p.064704_1 - 064704_6, 2018/06

https://doi.org/10.7566/JPSJ.87.064704

The ground states of the frustrated pyrochlore oxide TbTiO have been studied by inelastic neutron scattering experiments. Three single-crystal samples are investigated; one shows no phase transition (), being a putative quantum spin-liquid (QSL), and the other two () show electric quadrupole ordering (QO) below K. The QSL sample shows continuum excitation spectra with an energy scale 0.1 meV as well as energy-resolution-limited (nominally) elastic scattering. As is increased, pseudospin wave of the QO state emerges from this continuum excitation, which agrees with that of powder samples and consequently verifies good control for the present single crystal samples.