Structural dependent ultrafast electron-phonon coupling in multiferroic BiFeO 3 films

Authors

Zuanming Jin, Shanghai University
Yue Xu, Shanghai University
Zhengbing Zhang, Shanghai University
Gaofang Li, Shanghai University
Xian Lin, Shanghai University
Guohong Ma, Shanghai University
Zhenxiang Cheng, University of WollongongFollow
Xiaolin Wang, University of WollongongFollow

RIS ID

53012

Publication Details

Jin, Z., Xu, Y., Zhang, Z., Li, G., Lin, X., Ma, G., Cheng, Z.& Wang, X.(2012).Structural dependent ultrafast electron-phonon coupling in multiferroic BiFeO 3 films.Applied Physics Letters, 100 (7),

Abstract

The electronic energy relaxation of polycrystalline BiFeO3 films is studied using ultrafast pump-probe spectroscopy. After photo-excitation with femtosecond laser pulses, the relaxation of hot electrons is identified to decay with two different characteristic times. The fast process is attributed to scattering of electrons with lattice-vibration modes, and the slow one is corresponding to the spin-lattice thermalization. The electron-phonon coupling is characterized by the second moment of the Eliashberg function, khx2i. Due to the structural strain and symmetry breaking, the electron-phonon interaction strength of tetragonal BiFeO3 films is larger than that of rhombohedral counterparts