Abstract
Far-infrared reflection and ellipsometry measurements on multiferroic PrFe3(BO3)4 and SmFe3(BO3)4 single crystals were used to investigate the interaction between lattice phonons and electronic excitations associated with 4f crystal-field transitions. A temperature-dependent interference between two types of excitations was observed in PrFe3(BO3)4 in which the frequency of 4f crystal-field electronic excitation of Pr3+ falls into the TO-LO frequency interval of the optical phonon mode near 50 cm-1 (1.5 THz). Experimental data were explained on the basis of a theoretical model of coupled electron-phonon modes. The fitting procedure revealed the value 14.8 cm-1 for the electron-phonon coupling constant. This rather large value points to an essential role played by the electron-phonon interaction in the physics of multiferroics.
Original language | English (US) |
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Article number | 121101 |
Journal | Physical Review B - Condensed Matter and Materials Physics |
Volume | 90 |
Issue number | 12 |
DOIs | |
State | Published - Sep 2 2014 |
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics