実験報告書様式（一般利用課題・成果公開利用）（ ※本報告書は英語で記述してください。ただし、産業利用課題として採択されている方は日本語で記述していただいても結構です。 ）提出日 Date of Report

Experimental Report

2013/01/10

課題番号 Project No.

装置責任者 Name of responsible person

2012A0042

J. Suzuki

実験課題名 Title of experiment

装置名 Name of Instrument/（BL No.）
BL-15

実験責任者名 Name of principal investigator

実施日時 Date and time of Experiment

Y. Kousaka

2012/11/07〜11/12

所属 Affiliation

試料、実験方法、利用の結果得られた主なデータ、考察、結論等を、記述して下さい。（適宜、図表添付のこと）
Please report your samples, experimental method and results, discussion and conclusions. Please add figures andtables for better explanation.
1. 試料 Name of sample(s) and chemical formula, or compositions including physical form.
Cr1/3TaS2 (粉末)
MnSi (単結晶)2. 実験方法及び結果 （実験がうまくいかなかった場合、その理由を記述してください。）
Experimental method and results.

If you failed to conduct experiment as planned, please describe reasons.

Our aim for this experiment was to investigate the formation of helimagnetic ordering chiral magnetic soliton
lattice in chiral magnetic compounds: T1/3MS2(T: transition metals, M: Nb or Ta), and MnSi. These compounds
can form chiral helimagnetic ordering due to the competition between ferromagnetic exchange interaction andD-M interaction, The pitch angle of the helix is determined by the ratio of ferromagnetic exchange interaction
and D-M interaction. As a result, the period is hundreds of angstroms, and thermal neutron diffraction does
not have enough Q-resolution to separate fundamental Bragg and magnetic satellite peaks. Therefore, they
are often misinterpreted as a ferromagnetic compound. The chiral helimagnetic compounds are recently paiedattention due to theoretical prediction of formating chiral magnetic soliton lattice under an applied magnetic
field perpendicular to the helical axis. The period can be tunable with the amplitude of an applied magnetic
field, and it expects phenomena like new giant magneto resistive effect. To reveal the long periodic magnetic
structure, SANS experiments can be an answer.
In TAIKAN, we firstly performed powder SANS experiments in Cr1/3TaS2. To see the magnetic signals, wesubtract the intensity at lowest temperature from intensity at paramagnetic phase. The result is shown in Fig.
12. 実験方法及び結果（つづき） Experimental method and results (continued)
1. We can see a magnetic satellite peaks. However, the peak Q-position of the satellite depends on theextracted wavelength. Therefore, we need to retreat the data carefully.

(a) λ = 6 ~ 8 (b) λ = 7 ~ 8 

Fig. 1 Peak profiles around (0,0,0) reflection in Cr1/3TaS2.
Secondly, we performed single crystalline SANS experiments in MnSi. As MnSi has cubic symmetry, themagnetic satellite peaks can be observed (1,1,1) direction and its equivalent directions like (1,1,-1). If we apply
the magnetic field along (1,1,1), we can expect the higher harmonics like (3q,3q,3q) due to the chiral magneticsoliton. As shown Fig. 1 (a), we succeeded in observing helimagnetic satellites. However, we cannot detect thehigher harmonics. To detect the evidence of the soliton lattice, we need more statistics for minimizing theerror.
(b)

(a)

(1,1,-1)

H // (1,1,1)

H = 47.2 Oe, T = 28.5(5) KFig. 1 Intensity color maps around (0,0,0) reflection in MnSi.
2