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Magnetic phase separation in La1-xSrxCoO3 by 59Co NMR

P. L. Kuhns·M. J. R. Hoch·W. G. Moulton·A. P. Reyes J. Wu·C. Leighton
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Abstract

59Co NMR measurements on La1-xSrxCoO3 reported here establish unequivocally, for the first time, the coexistence of ferromagnetic regions, spin glass regions, and hole poor low spin regions at all x values from 0.1 to 0.5. A zero external field NMR spectrum, which is assigned to the ferromagnetic regions, has a spectral shape which is nearly x independent at 1.9 K, as are the relaxation times, T1 and T2. The integrated spectral area increases rapidly with x up to x=0.2 and then becomes almost constant for larger x. In a field of 9.97 T, a narrow NMR line is observed at 102 MHz, identical to that found in x=0 samples in previous work. The integrated intensity of this spectrum decreases rapidly with increasing x, and is ascribed to hole poor low spin regions. Beneath this spectrum, a third broad line, centered at 100 MHz, with shorter T1 and T2,. is assigned to a spin glass, intermediate spin phase.

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P. L. Kuhns, M. J. R. Hoch, W. G. Moulton, A. P. Reyes J. Wu, C. Leighton. 2003-01-28. Magnetic phase separation in La1-xSrxCoO3 by 59Co NMR. https://arxiv.org/abs/cond-mat/0301553

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