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Impurity susceptibility and the fate of spin-flop transitions in lightly-doped La(2)CuO(4)

M. B. Silva Neto·L. Benfatto
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Abstract

We investigate the occurrence of a two-step spin-flop transition and spin reorientation when a longitudinal magnetic field is applied to lightly hole-doped La(2)CuO(4). We find that for large and strongly frustrating impurities, such as Sr in La(2-x)Sr(x)CuO(4), the huge enhancement of the longitudinal susceptibility suppresses the intermediate flop and the reorientation of spins is smooth and continuous. Contrary, for small and weakly frustrating impurities, such as O in La(2)CuO(4+y), a discontinuous spin reorientation (two-step spin-flop transition) takes place. Furthermore, we show that for La(2-x)Sr(x)CuO(4) the field dependence of the magnon gaps differs qualitatively from the La(2)CuO(4) case, a prediction to be verified with Raman spectroscopy or neutron scattering.

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M. B. Silva Neto, L. Benfatto. 2007-02-02. Impurity susceptibility and the fate of spin-flop transitions in lightly-doped La(2)CuO(4). https://doi.org/10.1103/physrevb.75.140501

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