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
2011. 6. 30

課題番号 Project No.

装置責任者 Name of responsible person

2010A0078

Yasuhiro Miyake

実験課題名 Title of experiment
Effects of nonmagnetic, magnetic and electrostatic impurities on

装置名 Name of Instrument/（BL No.）

the Cu-spin correlation and superconductivity in high-Tc

D1

cuprates

実施日 Date of Experiment

実験責任者名 Name of principal investigator2010. 11. 16-19

Tadashi Adachi
所属 Affiliation
Department of Applied Physics, Graduate School of Engineering,Tohoku University
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.
La-based high-Tc superconducting cuprates
La2-xSrxCu1-y(Zn,Ni,Fe,Ga)yO4 with x = 0.08 - 0.11 and y = 0 - 0.03
Ceramic samples

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.

Zero-field SR measurements have been performed at temperatures between ~ 3 K and 20 K in
La2-xSrxCu1-y(Zn,Ni,Fe,Ga)yO4 with x = 0.08 - 0.11 and y = 0 - 0.03. Samples for measurements used in the
double-pulsed and single-pulsed mode are listed below.
For single-pulsed mode:Zn: x = 0.08; y = 0.01, 0.03
Ni: x = 0.09; y = 0.01
Fe: x = 0.085; y = 0.005, x = 0.09; y = 0.01, x = 0.11; y = 0.03
Ga: x = 0.09; y = 0.01, x = 0.11; y = 0.03
For double-pulsed mode:Zn: x = 0.08; y = 0.01
Fe: x = 0.085; y = 0.005, x = 0.09; y = 0.01, x = 0.11; y = 0.03
Ga: x = 0.09; y = 0.01

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2. 実験方法及び結果（つづき） Experimental method and results (continued)
Figure 1 shows the zero-field (ZF) SR time spectra measured in the double-pulsed mode of the 0.5 %Fe-substituted La2-xSrxCu1-yFeyO4 with x = 0.085 and y = 0.005.

At high temperatures of 17.8 K, thespectrum shows Gaussian-like slow depolarization due to randomly oriented nuclear spins. With decreasing
temperature, the spectrum changes from Gaussian-type to exponential-type and a muon-spin precession isobserved below 3.8 K, indicating the formation of a long-range magnetic order of Cu spins through 0.5 % Fesubstitution.
In order to investigate the precession spectra in detail, we have performed ZF-SR in the single-pulsed
mode by using the beam slicer. For 1 % substitution of Zn, Ni, Fe, Ga, all the samples show the muon-spin
precession at ~ 3 K. However, due to an instrumental problem, the attained lowest temperature is different
from each sample, preventing us from comparing explicitly the effects of nonmagnetic, magnetic andelectrostatic impurities on the Cu-spin correlation by focusing on an internal magnetic field, magnetic volume
fraction and damping rate. In order to obtain detailed information on them, improvements of the instrument
at D1 are desired.

Normalized Asymmetry

1.0

La2-xSrxCu1-yFeyO4
x = 0.085 y = 0.005

0.8

17.8 K13.410.8
9.1
7.4

0.6

6.5 K
5.6
4.2
3.8
2.8

0.4

0.2

002

468

10Time (sec)
Fig. 1. Zero-field SR time spectra of the 0.5 % Fe-substituted La2-xSrxCu1-yFeyO4 with x = 0.085 and y = 0.005.

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