Spin-charge-lattice coupling through resonant multimagnon excitations in multiferroic BiFeO{sub 3}

Spin-charge-lattice coupling mediated by multimagnon processes is demonstrated in multiferroic BiFeO{sub 3}. Experimental evidence of two- and three-magnon excitations as well as multimagnon coupling at electronic energy scales and high temperatures are reported. Temperature dependent Raman experiments show up to five resonant enhancements of the two-magnon excitation below the Neel temperature. These are shown to be collective interactions between on-site Fe d-d electronic resonance, phonons, and multimagnons.