Coherent Phonons and Magnons in Hetero-Epitaxial BTO-BFO Films and Nano-rods

The desire to create monolithic multifunctional devices has driven significant research toward exploring multiferroics, where the coupling between electric, magnetic, optical, and structural order parameters can provide added functionality. In this study, we utilize time resolved responses of (1-x)BaTiO₃(x)BiFeO₃, x = 0.725 epitaxial films grown on LSMO with STO substrate and the BTO-BFO nanorods grown on Pt with Si as the substrate to reveal several coherent dynamics. We probed the dynamics of photo-excited carriers in several films and nanorods to obtain information on the time scale of different relaxation process, including coherent phonon and magnon dynamics. The ability to generate and manipulate the time resolved, phononic, and magnonic degrees of freedom in materials with external optical, electric, and magnetic fields promises to usher in a new era of revolutionary.