Ueda, Hiroshi*; Onoda, Shigeki*; Yamaguchi, Yasuhiro*; Kimura, Tsuyoshi*; Yoshizawa, Daichi*; Morioka, Toshiaki*; Hagiwara, Masayuki*; Hagiwara, Masato*; Soda, Minoru*; Masuda, Takatsugu*; et al.
Physical Review B, 101(14), p.140408_1 - 140408_6, 2020/04
Ito, Shinichi*; Yokoo, Tetsuya*; Masuda, Takatsugu*; Yoshizawa, Hideki*; Soda, Minoru*; Ikeda, Yoichi*; Ibuka, Soshi*; Kawana, Daichi*; Sato, Taku*; Nambu, Yusuke*; et al.
JPS Conference Proceedings (Internet), 8, p.034001_1 - 034001_6, 2015/09
Hase, Masashi*; Dnni, A.*; Ozawa, Kiyoshi*; Kitazawa, Hideaki*; Sakai, Osamu*; Pomjakushin, V. Y.*; Keller, L.*; Kaneko, Koji; Metoki, Naoto; Kakurai, Kazuhisa; et al.
Journal of Physics; Conference Series, 340, p.012066_1 - 012066_7, 2012/00
We determined the magnetic structure below K of the spin-5/2 antiferromagnetic (AF) trimer substance SrMnPO using neutron powder diffraction experiments. The incommensurate propagation vector is expressed as [0, , 0], due to competition between the nearest-neighbor and next-nearest-neighbor interactions in trimerized chains. The value of is 0.316 to 0.331, changing rapidly at K. We confirmed that the intra-trimer interaction is AF. The magnetic excitation peaks were obsereved at 0.46, 0.68, and 1.02 meV. The weak Q dependence indicates the discrete energy levels, which do not contradict the AF trimer model with the intra-trimer interaction value of 0.29 meV (3.4 K).
Hase, Masashi*; Matsuda, Masaaki*; Kaneko, Koji; Metoki, Naoto; Kakurai, Kazuhisa; Yang, T.*; Cong, R.*; Lin, J.*; Ozawa, Kiyoshi*; Kitazawa, Hideaki*
Physical Review B, 84(21), p.214402_1 - 214402_6, 2011/12
Nakagawa, Hitoshi*; Inafuku, Masashi*; Kusaba, Makoto*; Yamaguchi, Hiroyasu*; Morishita, Toshikazu*; Morita, Ryohei*; Nishimura, Minoru*; Hoeman, S.*; Yokota, Yuichiro; Hase, Yoshihiro; et al.
JAEA-Review 2007-060, JAEA Takasaki Annual Report 2006, P. 72, 2008/03
no abstracts in English
Hase, Masashi*; Matsuda, Masaaki; Kakurai, Kazuhisa; Ozawa, Kiyoshi*; Kitazawa, Hideaki*; Tsujii, Naohito*; Dnni, A.*; Kuroe, Haruhiko*
Physical Review B, 76(13), p.134403_1 - 34403_5, 2007/10
The magnetism of -AgCuPO has been studied using inelastic neutron scattering and magnetic susceptibility measurements on powder sample. A well-defined symmetric broad inelastic peak was observed at 6.2meV energy transfer, indicating the existence of spin-gap excitation. From the Q-dependence of the inelastic magnetic intensities it is concluded that the strongest exchange interaction exists in the Cu-O-P-O-Cu path and that the antiferromagnetic alternating chain model with two exchange interactions values of 80 and 14K can quantitatively explain the experimental results.
Hase, Masashi*; Matsuda, Masaaki; Kakurai, Kazuhisa; Ozawa, Kiyoshi*; Kitazawa, Hideaki*; Tsujii, Naohito*; Dnni, A.*; Kono, Masanori*; Hu, X.*
Physical Review B, 76(6), p.064431_1 - 064431_5, 2007/08
The magnetism of spin-1/2 trimer chain system Cu(POOD) is studied by means of inelastic neutron scattering. A spin excitation gap of 9.8meV corresponding to singlet -triplet excitation is observed and together with the magnetization plateau data the AF exchange interaction parameters of the trimer system could be determined as J=111K and J=30K.
Nakagawa, Hitoshi*; Inafuku, Masashi*; Kusaba, Noboru*; Yamaguchi, Hiroyasu*; Morishita, Toshikazu*; Morita, Ryohei*; Nishimura, Minoru*; Hoeman, S.*; Yokota, Yuichiro; Hase, Yoshihiro; et al.
no journal, ,
no abstracts in English
Kakurai, Kazuhisa; Matsuda, Masaaki; Hase, Masashi*; Ozawa, Kiyoshi*; Kitazawa, Hideaki*; Tsujii, Naoto*; Doenni, A.*; Hu, X.*; Kuroe, Haruhiko*
no journal, ,
We report powder sample inelastic neutron scattering experiments on spin gap systems. Recently the magnetization plateau phenomenon in quantum spin systems are drawing attention of both theoretical and experimental physicists. Although the relevant exchange energies can be estimated from the magnetic susceptibility measurements assuming some theoretical models, we can only speculate the exchange interaction scheme causing the singlet ground state based on the structural and bonding information. We shall present examples of powder sample inelastic neutron scattering studies on the antiferromagnetic alternating chain system -AgCuPO and trimer chain compound Cu(POOD) using triple axis spectrometer at the steady state neutron source and stress that this kind of research on novel quantum systems could be very effectively performed using the low-energy chopper type spectrometer being built for the J-PARC spallation neutron source.
Kuroe, Haruhiko*; Hamasaki, Tomoyuki*; Hase, Masashi*; Kaneko, Koji; Metoki, Naoto; Matsuda, Masaaki; Kakurai, Kazuhisa; Oka, Kunihiko*; Ito, Toshimitsu*; Eisaki, Hiroshi*
no journal, ,
We have measured inelastic neutron scattering in CuMoO to study its magnetic-excitation dispersion curves. This material can be treated as a complex of the following two spin subsystems. (1) Quasi-one-dimensional antiferromagnetic (AF) spin chain with the intrachain interaction pJ4 = 6.3 meV, where p is the renormalization factor depending on the system dimension, together with the ferromagnetic and AF interchain interactions -Ja = J 0.01pJ4. (2) AF spin dimers with the interaction J3 = 5.8 meV. The hybridization parameter, representing the intersubsystem interaction between these subsystems, is estimated as Eint sin (k), where Eint = 1.6 meV. The modulation of the molecular field generated by the spin precession in the excited state of the quasi-one-dimensional spin chain plays an important role in this hybridization.