Coherent acoustic perturbation of second-harmonic generation in NiO

Second-harmonic generation can be a powerful tool to study illusive material properties such as antiferromagnetism in NiO. However, in time resolved measurements on such a semi-transparent material, generation of coherent acoustic phonons can lead to complex dynamics in the SHG response. Here we show, that these dynamics do not directly reflect dynamics of the antiferromagnetic order in NiO, but follow a frequency dependence that is purely defined by phase matching, which, maybe surprisingly, also differs from the well-known stimulated Brillouin scattering. 

Physical Review B 92, 094304 (2015) (external pagepublisher sitecall_made).