Muon-spin rotation study of magnetism in NaxCoO2 single crystals with 0.78≤x≤0.97

被引：11
作者：
Bernhard, C.
Niedermayer, Ch.
Drew, A.
Khaliullin, G.
Bayrakci, S.
Strempfer, J.
Kremer, R. K.
Chen, D. P.
Lin, C. T.
Keimer, B.
机构：
[1] Univ Fribourg, Dept Phys, CH-1700 Fribourg, Switzerland
[2] Fribourg Ctr Nanomat FriMat, CH-1700 Fribourg, Switzerland
[3] Max Planck Inst Solid State Res, D-70569 Stuttgart, Germany
[4] Paul Scherrer Inst, CH-5232 Villigen, Switzerland
来源：
EPL | 2007年 / 80卷 / 02期
关键词：
D O I：
10.1209/0295-5075/80/27005
中图分类号：
O4 [物理学];
学科分类号：
0702 ;
摘要：
By muon spin rotation we investigated the magnetic properties of a series of highly Na-doped NaxCoO2 single crystals with 0.78(1) <= x <= 0.97(1). Our data provide evidence for an intrinsically inhomogeneous magnetic state which can be described in terms of hole-doping (Na vacancy)-induced magnetic clusters that percolate at 1- x greater than or similar to 0.04 until they yield a bulk magnetic state near x= 0.78. Evidence for a strong (likely geometrical) frustration of the magnetic order is obtained from the anomalous doping dependence of the spin fluctuation rate (above the ordering temperature) which is strongly enhanced at x= 0.78 as compared to x= 0.97. Copyright (C) EPLA, 2007.
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页数：6
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