Two-magnon Raman scattering in a spin density wave antiferromagnet
نویسندگان
چکیده
We present the results for a model calculation of resonant two-magnon Raman scattering in a spin density wave (SDW) antiferromagnet. The resonant enhancement of the two-magnon intensity is obtained from a microscopic analysis of the photon-magnon coupling vertex. By combining magnon-magnon interactions with ‘triple resonance‘ phenomena in the vertex function the resulting intensity line shape is found to closely resemble the measured twomagnon Raman signal in antiferromagnetic cuprates. Both, resonant and non-resonant Raman scattering are discussed for the SDW antiferromagnet and a comparison is made to the conventional Loudon-Fleury theory of twomagnon light scattering. PACS numbers: 75.30.Ds, 75.30.Fv, 76.50.+g
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