Detection of coherent magnons via ultrafast pump-probe reflectance   spectroscopy in multiferroic Ba0.6Sr1.4Zn2Fe12O22
  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. 
D. Talbayev, S. A. Trugman, A. V. Balatsky, T. Kimura, A. J. Taylor,   and R. D. Averitt