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One-magnon Raman scattering in La(2)CuO(4): the origin of the field-induced mode

M. B. Silva Neto·L. Benfatto
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Abstract

We investigate the one-magnon Raman scattering in the layered antiferromagnetic La(2)CuO(4) compound. We find that the Raman signal is composed by two one-magnon peaks: one in the B1g channel, corresponding to the Dzyaloshinskii-Moryia (DM) mode, and another in the B3g channel, corresponding to the XY mode. Furthermore, we show that a peak corresponding to the XY mode can be induced in the planar (RR) geometry when a magnetic field is applied along the easy axis for the sublattice magnetization. The appearance of such field-induced mode (FIM) signals the existence of a new magnetic state above the Neel temperature T_N, where the direction of the weak-ferromagnetic moment (WFM) lies within the CuO(2) planes.

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M. B. Silva Neto, L. Benfatto. 2005-10-11. One-magnon Raman scattering in La(2)CuO(4): the origin of the field-induced mode. https://doi.org/10.1103/physrevb.72.140401

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