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吉良 弘; 坂口 佳史; 奥 隆之; 鈴木 淳市; 中村 充孝; 新井 正敏; 加倉井 和久; 遠藤 康夫; 有本 靖*; 猪野 隆*; et al.
Physica B; Condensed Matter, 406(12), p.2433 - 2435, 2011/06
被引用回数：8 パーセンタイル：36.17(Physics, Condensed Matter)Polarized neutron scattering techniques are very important and powerful tools to study the fundamental structures of magnetic materials and soft matters. 
He has a very large absorption cross section for only neutrons in opposite spin state to that of the He nucleus. The scattering cross section of He is small. These two features allow nuclear spin polarized He gas to work as a NSF. Compared with other spin filters such as Heusler alloys and magnetic supermirrors, the He gas NSF have following advantages: it can polarize various energy of neutron such as cold, thermal and hot neutrons, it can work for broadband neutrons and it can be used for wide area and large divergence neutron beams. These characteristics of polarized He are convenient in use with J-PARC as NSF. We began the development of the on beam SEOP system aiming to use it s a NSF for incident beam polarisation and polarisation analysis. In this paper, we report the current development of SEOP system in Japan.
He neutron spin filters坂口 佳史; 吉良 弘; 奥 隆之; 篠原 武尚; 鈴木 淳市; 酒井 健二; 中村 充孝; 鈴谷 賢太郎; 相澤 一也; 新井 正敏; et al.
Physica B; Condensed Matter, 406(12), p.2443 - 2447, 2011/06
Polarized He neutron spin filters have attracted much attention because of their available wide energy range for polarizing neutrons and their large solid-angle. To use He neutron spin filters for the experiments, it is necessary to produce glass cells with good quality. For this purpose, we made research on the glass cells from several aspects. Firstly, we investigated on the microscopic structure for several glasses by means of X-ray diffraction measurement and tried to find a good measure of evaluating the quality of the cells in terms of their structure. Secondly, we investigated on the glass window, which the laser beam passes through for optical pumping. Thirdly, the cells should be optimized for the polarized neutron scattering experiments and the background from the cells needs to be evaluated. The scattered intensity from the cell in small-angle neutron scattering will also be presented.
Y
Ti
O
Chang, L.-J.; Su, Y.*; Kao, Y.-J.*; Chou, Y. Z.*; Mittal, R.*; Schneider, H.*; Brueckel, T.*; Balakrishnan, G.*; Lees, M. R.*
no journal, ,
Diffuse polarized neutron scatterings have been carried out on the pyrochlore spin ice HoYTiO (x = 0, 0.3 and 1) single crystals to investigate the doping effects and anisotropy of spin correlations in the system. The crystals were aligned in the (1-10) orientation to coincide with the direction of neutron polarization. The spin flip diffuse scattering (i.e. the in-plane component) reveals an anomalous crossover in the spin correlations from the nearest-neighbor spin ice correlation to a typical dipolar spin ice correlation as the temperature is reduced for all the samples. A signature of strong antiferromagnetic correlation is observed in the non-spin flip channel (i.e. the out-of-plane component), at the same temperatures where the dipolar spin ice correlation appears in the spin flip channel.
奥 隆之; 鈴木 淳市; 吉良 弘; 篠原 武尚; 高田 慎一; 新井 正敏; 広田 克也*; 岩下 芳久*; 清水 裕彦*
no journal, ,
中性子の磁気モーメントと磁場との相互作用を利用することにより、中性子スピンに対して選択的な輸送やビーム整形を行うことができる。また、磁場を用いた中性子ビーム整形は、多重極磁石を複数組合せて用いることにより、自由度が増す。これまでにわれわれは、四極磁石と六極磁石を組合せた偏極中性子集光システムを開発し、原子力機構の中性子小角散乱装置に導入し、その実用化に成功した。そこで、今回、四極磁石と六極磁石からなる偏極中性子集光システムの適用範囲の拡大を目的として、大口径四極磁石の開発を行った。会議では、開発した大口径四極磁石の性能について紹介するとともに、その応用研究について議論する。
武田 全康; 丸山 龍治; 相澤 一也; 新井 正敏; 金子 耕士; 中谷 健; 篠原 武尚; 鈴木 淳市; 鈴谷 賢太郎; 高橋 伸明; et al.
no journal, ,
A new polarized neutron reflectometer is now under construction at Materials and Life Science Facility (MLF) of Japan Proton Accelerator Research Complex (J-PARC). MLF has an intense pulsed neutron source, and the user program has been already started in 2009 using 8 spectrometers. Installation of the new reflectometer is expected to be completed on March 2011. The outline design specification of this new polarized neutron reflectometer will be presented at the conference.
加倉井 和久
no journal, ,
In studying modern functional materials, one is often confronted with complex spin configurations, for example, non-collinear, incommensurate magnetic structure such as helimagnetic structure as a result of frustrated magnetic interactions. Since the giant functional responses in these materials are direct consequences of these complicated magnetic structures, the detailed knowledge of the structure is mandatory to understand the essence of the magnetic functional materials. In this talk some recent polarized neutron scattering results on complex magnetic materials such as frustrated and multiferroic systems are presented, where the polarized neutron investigations provided important insight into the complex behavior of these functional materials.
