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。 ）MLF Experimental Report

提出日 Date of Report

2014/9/5

課題番号 Project No.

装置責任者 Name of Instrument scientist

2014A0205

幸田章宏、宮崎正範

実験課題名 Title of experiment

装置名 Name of Instrument/（BL No.）Special spin density distribution in T'-sturctured cuprate

D1oxides studied by µSR

実施日 Date of Experiment

実験責任者名 Name of principal investigator2014 5/24-26

藤田全基
所属 Affiliation
東北大学
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.
Pr1.40La0.60CuO4 (as-sintered)
Pr1.32La0.60Ce0.08CuO4 (as-sintered)Pr1.24La0.60Ce0.16CuO4 (as-sintered)
Eu2CuO4 (as-sintered)

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.

Experimental method
We performed zero field and transverse field µSR measurements on the as-sintered Pr1.4-xLa0.6CexCuO4(PLCCO) (x=0, 0.08, 0.16) and Eu2CuO4 samples at low temperatures (12 K) to investigate the magnetic
properties in the T’-structured cuprate oxide.
Experimental Results
Figure 1 shows the field-dependence (Bext) of muon polarization rate along the field direction (Pz) for the x=0and 0.16 samples measured at low temperature. The field-dependence of Pz in Pr1.4La0.6CuO4 cannot be
reproduced by assuming the single muon stopping site. This suggests the existence of two muon stoppingsites in the x=0 sample and the different magnetic fields at these sites. In fact, the field dependence of Pz iswell reproduce by taking the two field distribution into account. On the other hand, Pz in the PLCCO with
x=0.16 sample as a function of field is reasonably fitted by assuming the single muon site and/or two sites
12. 実験方法及び結果（つづき） Experimental method and results (continued)(b) Pr1.24La0.6Ce0.16CuO4+ as-sinteredδ.

Figure1: Field-dependence of muon polarization rate for the as-sintered (a) Pr1.40La0.60CuO4 and (b)Pr1.24La0.60Ce0.16CuO4 samples.

with the comparable magnetic fields. Figure 2 shows the Fourier transform of muon time spectrum. The field
distribution in Pr1.40La0.60CuO4 shows well-defined
two peaks, while that in Pr1.24La0.60Ce0.16CuO4 has abroad peak. Interestingly, the field distribution in
Eu2CuO4 shows a sharp single peak, which is incontrast to the spectrum in Pr1.40La0.60CuO4, althoughboththeyaretheundopedcompound. Thisdifference can be explained through the size of rearearth moment. We evaluated the magnetic fields at
the muon stopping sites and confirmed that thecomparable magnetic fields is induced at the muonsites in the case of non-magnetic rear earth ion. With
increasing the moment size of rear earth ion, thedifference of magnetic field at two muon sites
becomes large, consistent with our observation in
the Pr1.40La0.60CuO4. Therefore, our result in thePr1.24La0.60Ce0.16CuO4 suggests that the Pr moment isreduced by Ce doping. Since the electron carrier isFigure 2: The real part of Fourier transform of muon

doped by Ce substitution, the mobile carriers
degrade the magnetic interaction between Pr and Cutime spectrum for (a) Eu2CuO4 (b) Pr1.40La0.60CuO4ions, possibly resulting into the paramagneticand (c) Pr1.24La0.60Ce0.16CuO4 at 12 K.

fluctuation of Pr ions.

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