Ultrafast electron-phonon coupling and photo-induced strain in the morphotropic phase boundary of BixDy1−xFeO3 films

• Main Authors: Zhang, Zeyu, You, Lu, Du, Juan, Wang, Junling, Jin, Zuanming, Ma, Guohong, Leng, Yuxin
• Other Authors: School of Materials Science & Engineering
• Format: Article
• Language: English
• Published: 2018
• Subjects: Morphotropic Phase Boundary; Ultrafast Photonics
• Online Access: https://hdl.handle.net/10356/87557; http://hdl.handle.net/10220/45405
• Institution: Nanyang Technological University

The interplay among ferroelectric, magnetic and elastic degrees of freedom in multiferroics is the key issues in condensed matters, which has been widely investigated by various methods. Here, using ultrafast two-color pump-probe spectroscopy, the picosecond electron-phonon and spin-lattice coupling process in Dysprosium doped-BiFeO3 (BDFO) films on SrTiO3 (STO) substrate have been investigated systematically. The Dy-doping induced structural transition and magnetic enhancement in BDFO is observed by ultrafast electron-phonon and spin-lattice interaction, respectively. The elastic anomalies in BDFO films are revealed by the photo-induced coherent acoustic phonon. With increasing the Dy doping ratio, the frequencies of the acoustic phonon in the films are modulated, and the phonon transmission coefficient between films and substrate is found to approach unity gradually. The ultrafast observation of the tunability of the ferroelectric, magnetic and the elastic properties in the morphotropic phase boundary of rare-earth doped BFO films provides new insights into the integration of BFO in next-generation high frequency electro-magnetic and electroacoustic devices.