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arXiv · 1510.06244

Magnetic phase diagram of La$_{2-x}$Sr$_{x}$CoO$_{4}$ revised using muon-spin relaxation

R. C. Williams·F. Xiao·T. Lancaster·R. De Renzi·G. Allodi·S. Bordignon·P. G. Freeman·F. L. Pratt·S. R. Giblin·J. S. Möller·S. J. Blundell·A. T. Boothroyd·D. Prabhakaran
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Abstract

We report the results of a muon-spin relaxation ($μ$SR) investigation of La$_{2-x}$Sr$_{x}$CoO$_{4}$, an antiferromagnetic insulating series which has been shown to support charge ordered and magnetic stripe phases and an hourglass magnetic excitation spectrum. We present a revised magnetic phase diagram, which shows that the suppression of the magnetic ordering temperature is highly sensitive to small concentrations of holes. Distinct behavior within an intermediate $x$ range ($0.2 \leq x \lesssim 0.6$) suggests that the putative stripe ordered phase extends to lower $x$ than previously thought. Further charge doping ($0.67 \leq x \leq 0.9$) prevents magnetic ordering for $T \gtrsim 1.5~{\rm K}$

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R. C. Williams, F. Xiao, T. Lancaster, R. De Renzi, G. Allodi, S. Bordignon, P. G. Freeman, F. L. Pratt, S. R. Giblin, J. S. Möller, S. J. Blundell, A. T. Boothroyd, D. Prabhakaran. 2015-10-21. Magnetic phase diagram of La$_{2-x}$Sr$_{x}$CoO$_{4}$ revised using muon-spin relaxation. https://doi.org/10.1103/physrevb.93.140406

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