High-temperature (295 - 1000 K) Raman studies of Nd-doped bismuth ferrite epitaxial heterostructures were performed. The bands 620 cм-1 and 1260 cm-1 were observed in the high-frequency range above the first-order phonons. The band 620 cм-1 corresponds to the maximum density of states of magnon branch at the Brillouin zone boundary. The intense second-order band at about 1260 cm-1 corresponds to the density of states of two-magnon excitations. The intensity of two-magnon scattering decreases with increasing temperature, and above the Neel temperature paramagnon scattering typical for antiferromagnetics was observed.

Keywords: Raman spectroscopy, multiferroic, bismuth ferrite, heterostructure