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arXiv · 0902.1788

59Co and 75As NMR Investigation of the Lightly Doped Ba[Fe(1-x)Co(x)]2As2 (x =0.02, 0.04)

F. L. Ning·K. Ahilan·T. Imai·A. S. Sefat·R. Jin·M. A. McGuire·B. C. Sales·D. Mandrus
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Abstract

We investigate the electronic properties of Ba[Fe(1-x)Co(x)]2As2 (x =0.02, 0.04) in the lightly electron-doped regime by 59Co and 75As NMR. We demonstrate that Co doping significantly suppresses the magnetic ordering temperature to the SDW state, T_{SDW}. Furthermore, ordered moments below T_{SDW} exhibit large distribution. Strong spin fluctuations remain even below T_{SDW}, persisting all the way down to 4.2 K. We find no signature of additional freezing of spin degrees of freedom unlike the case of the lightly hole-doped stripe phase of the cuprates.

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F. L. Ning, K. Ahilan, T. Imai, A. S. Sefat, R. Jin, M. A. McGuire, B. C. Sales, D. Mandrus. 2009-04-23. 59Co and 75As NMR Investigation of the Lightly Doped Ba[Fe(1-x)Co(x)]2As2 (x =0.02, 0.04). https://doi.org/10.1103/physrevb.79.140506

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