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arXiv · 0909.0876

Crossover of the dimensionality of 3d spin fluctuations in LaCoPO

M. Majumder·K. Ghoshray·A. Ghoshray·B. Bandyopadhyay·B. Pahari·S. Banerjee
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Abstract

dc magnetization and 31^P spin lattice relaxation rate in the polycrystalline sample of LaCoPO suggest a spin fluctuation dominated ferromagnetically ordered state. Moreover, NMR data clearly indicate a crossover from 2D to 3D spin fluctuations across T_C. In contrast to isotropic hyperfine field, H_hf at the 31^P site in LaFePO, H_hf is anisotropic in LaCoPO. The data of spin lattice relaxation rate also exhibit anisotropic spin fluctuation. The anisotropy vanishes near T_C.

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M. Majumder, K. Ghoshray, A. Ghoshray, B. Bandyopadhyay, B. Pahari, S. Banerjee. 2009-09-04. Crossover of the dimensionality of 3d spin fluctuations in LaCoPO. https://doi.org/10.1103/physrevb.80.212402

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