  We report the detection of a magnetic resonance mode in multiferroic
Ba0.6Sr1.4Zn2Fe12O22 using time domain pump-probe reflectance spectroscopy.
Magnetic sublattice precession is coherently excited via picosecond thermal
modification of the exchange energy. Importantly, this precession is recorded
as a change in reflectance caused by the dynamic magnetoelectric effect. Thus,
transient reflectance provides a sensitive probe of magnetization dynamics in
materials with strong magnetoelectric coupling, such as multiferroics,
revealing new possibilities for application in spintronics and ultrafast
manipulation of magnetic moments.
