NMR Study of Magnetic Properties in La_(2-x)Sr_xNiO_4
Abstract
The interaction between doped holes and spin fluctuations induced by the magnetic moments in transition metal based perovskite compounds is an attractive subject related to the understanding of high Tc superconductivity. La_2-xSr_xNiO4 is one of the materials that possess the same crystal structure as superconducting La_2-xSr_xCuO_4, but hole doping does not lead to either a metallic state or superconductivity. Recently, a charge ordering has been found by electron diffraction in La_2-xSr_xNiO4 with x=1/3 and 1/2.(C.H. Chen, S-W. Cheong and A.S. Cooper, PRL 71, 2461 (1993)) (S-W. Cheong et al.), Physica B 199&200, 659 (1994) The ordering occurs in such a way that one dimensional stripe of the localized holes extends along the diagonal direction in the NiO2 square and each of them is equally separated in space. We will present ^139La NMR results on this compound. The spin-lattice relaxation rate (T_1-1) clearly shows a critical slowing down toward a magnetic phase transition. The ^139La NMR spectra reveal an unusual lineshape well above T_N. Those results will be discussed in connection with the charge stripe ordering.
- Publication:
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APS March Meeting Abstracts
- Pub Date:
- March 1997
- Bibcode:
- 1997APS..MAR.G1101H