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He neutron spin filter at J-PARCTakahashi, Shingo; Kiyanagi, Ryoji; Okudaira, Takuya*; Takada, Shusuke*; Kobayashi, Ryuju; Okuizumi, Mao; Ino, Takashi*; Asai, Kanta*; Tsuchikawa, Yusuke; Oikawa, Kenichi; et al.
Nuclear Instruments and Methods in Physics Research A, 1075, p.170410_1 - 170410_8, 2025/06
Times Cited Count:0 Percentile:0.00(Instruments & Instrumentation)Sakai, Kenji; Oku, Takayuki; Okudaira, Takuya; Kai, Tetsuya; Harada, Masahide; Hiroi, Kosuke; Hayashida, Hirotoshi*; Kakurai, Kazuhisa*; Shimizu, Hirohiko*; Hirota, Katsuya*; et al.
JPS Conference Proceedings (Internet), 33, p.011116_1 - 011116_6, 2021/03
In neutron fundamental physics, study of correlation term
of a neutron spin
and a target nuclear spin
is important because
term interferes to parity non-conserving (PNC) and time reversal non-conserving terms. For this study, a xenon (Xe) is an interesting nucleus because it has been observed an enhancement of PNC effect around neutron resonance peaks, and polarizes up to
by using a spin exchange optical pumping (SEOP) method. We would plan to develop a polarized Xe gas target with a compact in-situ SEOP system, and to study
term by utilizing epithermal neutron beams supplied from a high intense pulsed spallation neutron source. As the first step, we attempted to measure neutron polarizing ability caused by
term at a 9.6 eV s-wave resonance peak of
Xe at BL10 in MLF, by detecting change
of ratio between neutron transmissions with the polarized and unpolarized Xe target. After demonstrating that our apparatus could detect small change (
) of neutron transmissions caused by Doppler broadening effect, a signified value of
has been obtained as preliminary results. For analyzing the obtained
in detail, we are improving our nuclear magnetic resonance and electron paramagnetic resonance systems for evaluating Xe polarization independently of neutron beams.
He neutron spin filter and magnetic super-mirrorsOkudaira, Takuya; Oku, Takayuki; Sakai, Kenji; Hiroi, Kosuke; Shinohara, Takenao; Ino, Takashi*; Kira, Hiroshi*; Hayashida, Hirotoshi*; Suzuki, Junichi*; Kakurai, Kazuhisa*; et al.
JPS Conference Proceedings (Internet), 33, p.011096_1 - 011096_6, 2021/03
We have been developing a
He neutron spin filter (NSF) for efficient utilization of pulsed neutrons at J-PARC MLF, since it can polarize neutrons effectively in a wide energy range. We performed demonstrative experiments using the
He-NSF at small-angle scattering (BL15 TAIKAN), reflection (BL17 SHARAKU) and imaging instrument (BL22 RADEN) of J-PARC MLF, and got reasonable results. Then, we have performed a demonstrative study of polarized-neutron single-crystal diffraction measurement at BL18 (SENJU). The sample was a single crystal Fe. As the result, expected flipping ratios of Bragg beaks were not observed. Therefore, we have performed a depolarization experiment of neutrons transmitted through the sample, and found out neutron severe depolarization occurred in the sample which was almost magnetically saturated under an applied magnetic field of 4.2 k Gauss. In this paper, we will show the experimental results of the depolarization experiment of neutrons transmitted through the single crystal Fe and discuss them.
He neutron spin filter at J-PARCOkudaira, Takuya; Oku, Takayuki; Ino, Takashi*; Hayashida, Hirotoshi*; Kira, Hiroshi*; Sakai, Kenji; Hiroi, Kosuke; Takahashi, Shingo*; Aizawa, Kazuya; Endo, Hitoshi*; et al.
Nuclear Instruments and Methods in Physics Research A, 977, p.164301_1 - 164301_8, 2020/10
Times Cited Count:21 Percentile:88.43(Instruments & Instrumentation)Nambu, Yusuke*; Barker, J.*; Okino, Yuki*; Kikkawa, Takashi*; Shiomi, Yuki*; Enderle, M.*; Weber, T.*; Winn, B.*; Graves-Brook, M.*; Tranquada, J. M.*; et al.
Physical Review Letters, 125(2), p.027201_1 - 027201_6, 2020/07
Times Cited Count:69 Percentile:95.26(Physics, Multidisciplinary)
=0 long-range magnetic order in centennialite CaCu
(OD)
Cl
0.6D
O; A Spin-
perfect kagome antiferromagnet with
-
-
Iida, Kazuki*; Yoshida, Hiroyuki*; Nakao, Akiko*; Jeschke, H. O.*; Iqbal, Y.*; Nakajima, Kenji; Kawamura, Seiko; Munakata, Koji*; Inamura, Yasuhiro; Murai, Naoki; et al.
Physical Review B, 101(22), p.220408_1 - 220408_6, 2020/06
Times Cited Count:29 Percentile:78.16(Materials Science, Multidisciplinary)Crystal and magnetic structures of the mineral centennialite CaCu
(OD)
Cl
0.6D
O are investigated by means of synchrotron X-ray diffraction and neutron diffraction measurements complemented by density functional theory (DFT) and pseudofermion functional renormalization group (PFFRG) calculations. In CaCu
(OD)
Cl
0.6D
O, Cu
ions form a geometrically perfect kagome network with antiferromagnetic
. No intersite disorder between Cu
and Ca
ions is detected. CaCu
(OD)
Cl
0.6D
O enters a magnetic long-range ordered state below
= 7.2 K, and the
=0 magnetic structure with negative vector spin chirality is obtained. The ordered moment at 0.3 K is suppressed to 0.58(2)
B. Our DFT calculations indicate the presence of antiferromagnetic
and ferromagnetic
superexchange couplings of a strength which places the system at the crossroads of three magnetic orders (at the classical level) and a spin-
PFFRG analysis shows a dominance of
=0 type magnetic correlations, consistent with and indicating proximity to the observed
=0 spin structure. The results suggest that this material is located close to a quantum critical point and is a good realization of a
-
-
kagome antiferromagnet.
RuO
proved by spin resonanceIida, Kazuki*; Kofu, Maiko; Suzuki, Katsuhiro*; Murai, Naoki; Kawamura, Seiko; Kajimoto, Ryoichi; Inamura, Yasuhiro; Ishikado, Motoyuki*; Hasegawa, Shunsuke*; Masuda, Takatsugu*; et al.
Journal of the Physical Society of Japan, 89(5), p.053702_1 - 053702_5, 2020/05
Times Cited Count:23 Percentile:76.34(Physics, Multidisciplinary)Okudaira, Takuya; Oku, Takayuki; Sakai, Kenji; Ino, Takashi*; Hayashida, Hirotoshi*; Hiroi, Kosuke; Shinohara, Takenao; Kakurai, Kazuhisa*; Aizawa, Kazuya; Shimizu, Hirohiko*; et al.
Proceedings of Science (Internet), 356, p.029_1 - 029_5, 2019/12
The technology development section carries out the development of the neutron polarization device:
He Spin Filter. It is often used for the fundamental physics region. In order to explain the matter-dominated universe, a time reversal violation is necessary and searches for new physics are conducted in the world. The T-violation search using a polarized neutron beam is planned at J-PARC. A large
He spin filter is needed to polarize high energy neutrons for the experiment and is developed in JAEA. Recently, we developed the accurate measurement system to evaluate the polarization of
He and a vacuum system to make the
He spin filter, and large
He spin filters for epi-thermal neutron was made using the system. The current status of the development of the
He spin filter will be talked.
Nakajima, Taro*; Inamura, Yasuhiro; Ito, Takayoshi*; Oishi, Kazuki*; Oike, Hiroshi*; Kagawa, Fumitaka*; Kikkawa, Akiko*; Taguchi, Yasujiro*; Kakurai, Kazuhisa*; Tokura, Yoshinori*; et al.
Physical Review B, 98(1), p.014424_1 - 014424_5, 2018/07
Times Cited Count:9 Percentile:35.62(Materials Science, Multidisciplinary)We investigated the phase-transition kinetics of magnetic skyrmion lattice (SkL) in MnSi by means of stroboscopic small-angle neutron scattering (SANS). Temporal evolutions of SANS patterns were measured with time resolution of 13 ms while sweeping temperature as fast as 50 Ks
. It turned out that the paramagnetic-to-SkL transition immediately occurs upon traversing the equilibrium phase boundary on the rapid cooling, whereas the SkL-to-conical transition can be kinetically avoided to realize the low-temperature metastable SkL with a long-range magnetic order. The formation of the metastable SkL was found to be strongly dependent not only on cooling rate, but also on magnetic eld and trajectory in the H-T phase diagram.
CoSb
O
Ito, Saya*; Kurita, Nubuyuki*; Tanaka, Hidekazu*; Kawamura, Seiko; Nakajima, Kenji; Ito, Shinichi*; Kuwahara, Keitaro*; Kakurai, Kazuhisa*
Nature Communications (Internet), 8, p.235_1 - 235_6, 2017/08
Times Cited Count:98 Percentile:94.49(Multidisciplinary Sciences)
O
by dynamical Jahn-Teller effectKamazawa, Kazuya*; Ishikado, Motoyuki*; Kawamura, Seiko; Kawakita, Yukinobu; Kakurai, Kazuhisa*; Nakajima, Kenji; Sato, Masashi*
Physical Review B, 95(10), p.104413_1 - 104413_7, 2017/03
Times Cited Count:2 Percentile:9.80(Materials Science, Multidisciplinary)
He Neutron Spin Filter (NSF) in the MLF at J-PARCSakai, Kenji; Oku, Takayuki; Hayashida, Hirotoshi*; Kira, Hiroshi*; Hiroi, Kosuke; Ino, Takashi*; Oyama, Kenji*; Okawara, Manabu*; Kakurai, Kazuhisa; Shinohara, Takenao; et al.
JPS Conference Proceedings (Internet), 8, p.036015_1 - 036015_6, 2015/09
The polarized
He filter, which polarizes neutrons due to a large neutron absorption cross section of
He with strong spin selectivity, becomes a convenient neutron spin filter (NSF) because it is operated immediately after its installation in beam lines without any neutron beam adjustments. For realizing such the NSF, a nuclear magnetic resonance (NMR) system is indispensable for monitoring
He nuclear spin polarization
of the NSF. We have developed the flexible NMR system based on adiabatic fast passage (AFP) and pulse NMR methods by using their complementary features. In comparing with the values of
obtained by neutron transmission measurement at the beam line 10 of the J-PARC, we measured the correlations between the AFP and pulse NMR signals as changing condition of temperature, amplitude and applying period of the radio frequency field for the pulse NMR, and so on. As the results, we confirmed that our system would function enough as the
monitor.
ZrCuO
with incommensurate magnetic structureYasui, Yukio*; Igawa, Naoki; Kakurai, Kazuhisa
JPS Conference Proceedings (Internet), 8, p.034012_1 - 034012_6, 2015/09
Magnetic structure has been studied by using neutron diffraction for quasi one-dimensional quantum spin system Li
ZrCuO
with CuO
ribbon chains. The CuO
ribbon system Li
ZrCuO
exhibits the antiferromagnetic transition at T
7 K, however, the magnetic transition is not accompanied with ferroelectricity. At 3K, we observed magnetic superlattice reflections at Q = (0, k, l
) and (h, 0, l
) (h, k and l = even) with 
0.488 by the powder neutron diffraction. By the combined studies of neutron diffraction and magnetization data, the magnetic structure of Li
ZrCuO
is proposed. On the bases of the obtained data, reasons for absence of ferroelectricity in Li
ZrCuO
are discussed.
He neutron spin filter and its application to magnetic field imaging at J-PARCSakai, Kenji; Oku, Takayuki; Hayashida, Hirotoshi; Kira, Hiroshi*; Shinohara, Takenao; Oikawa, Kenichi; Harada, Masahide; Kakurai, Kazuhisa; Aizawa, Kazuya; Arai, Masatoshi; et al.
Journal of Physics; Conference Series, 528, p.012016_1 - 012016_7, 2014/07
Times Cited Count:2 Percentile:66.85(Optics)In polarized neutron experiments, it is interested in expanding measurable neutron energy region up to epithermal neutrons. For realizing this situation, a Polarized
He Spin Flipper (PHSF) has a key role because it can polarize from cold to epithermal neutrons, and flip neutron spins by flipping the
He nuclear spin direction. We have developed the portable PHSF consisting of a cylindrical glass cell filled with
He gas which is installed a solenoid coil of 20 cm in diameter and 30 cm long. After polarizing the
He gas by irradiating a laser light based on a SEOP technique, the PHSF is brought by hands to experimental areas with kept its polarization. We carried out the feasibility test on our portable PHSF in the MLF of J-PARC and demonstrated it worked well by evaluating flipping ratios of polarized neutrons and attempting to visualize magnetic fields generated by sample coils.
ions for LaCo
Rh
O
Asai, Shinichiro*; Okazaki, Ryuji*; Terasaki, Ichiro*; Yasui, Yukio*; Igawa, Naoki; Kakurai, Kazuhisa
JPS Conference Proceedings (Internet), 3, p.014034_1 - 014034_6, 2014/06
We have carried out the neutron scattering measurements for a single crystal of LaCo
Rh
O
in order to investigate the ferromagnetic ordering induced by Rh
substitution for Co
of LaCoO
. The ordered moment is evaluated to be 0.4
0.2
, which is consistent with the saturation magnetization of LaCo
Rh
O
. It indicates that the ferromagnetic ordering of LaCo
Rh
O
originates from the short-range ferromagnetic ordering disordered by Rh
ions.
He spin filter system for neutron spin analyzer on the SHARAKU polarized neutron reflectometer at J-PARCHayashida, Hirotoshi; Oku, Takayuki; Kira, Hiroshi*; Sakai, Kenji; Takeda, Masayasu; Sakaguchi, Yoshifumi*; Ino, Takashi*; Shinohara, Takenao; Oyama, Kenji*; Suzuki, Junichi*; et al.
Journal of Physics; Conference Series, 528, p.012020_1 - 012020_7, 2014/00
no abstracts in English
O
Wakimoto, Shuichi; Kimura, Hiroyuki*; Sakamoto, Yuma*; Fukunaga, Mamoru*; Noda, Yukio*; Takeda, Masayasu; Kakurai, Kazuhisa
Physical Review B, 88(14), p.140403_1 - 140403_5, 2013/10
Times Cited Count:22 Percentile:63.65(Materials Science, Multidisciplinary)
Kajimoto, Ryoichi; Nakajima, Kenji; Kawamura, Seiko; Inamura, Yasuhiro; Kakurai, Kazuhisa; Hokazono, Takahisa*; Ozono, Akira*; Okuda, Tetsuji*
Journal of the Physical Society of Japan, 82(5), p.054702_1 - 054702_6, 2013/05
Times Cited Count:5 Percentile:37.11(Physics, Multidisciplinary)
O
Kambe, Takashi*; Fukada, Yukimasa*; Kano, Jun*; Nagata, Tomoko*; Okazaki, Hiroyuki*; Yokoya, Takayoshi*; Wakimoto, Shuichi; Kakurai, Kazuhisa; Ikeda, Naoshi*
Physical Review Letters, 110(11), p.117602_1 - 117602_5, 2013/03
Times Cited Count:26 Percentile:74.82(Physics, Multidisciplinary)
Ga
O
(x =0, 0.018)Nakajima, Taro*; Mitsuda, Setsuo*; Takahashi, Keiichiro*; Yoshitomi, Keisuke*; Masuda, Kazuya*; Kaneko, Chikafumi*; Homma, Yuki*; Kobayashi, Satoru*; Kitazawa, Hideaki*; Kosaka, Masashi*; et al.
Journal of the Physical Society of Japan, 81(9), p.094710_1 - 094710_8, 2012/09