Magnetically Controlled Surface Acoustic Waves on Multiferroic BiFeO₃

We fabricate a surface acoustic wave (SAW) device on a multiferroic BiFeO₃ crystal while SAW devices are usually fabricated on nonmagnetic piezoelectrics and commercially available as bandpass filters. By using the time-domain technique, we demonstrate the SAW excitation on BiFeO₃. The amplitude and phase of the SAW signal are modulated by the external magnetic field reflecting the multiferroicity of BiFeO₃. The magnetic controllability of the multiferroic SAW device seems useful for the further functionalization of the SAW device.