Impulsive stimulated Brillouin scattering in KD2PO4near the structural phase transition

Impulsive stimulated Brillouin scattering is used to characterize anomalous and highly dispersive acoustic behavior, including heavily overdamped acoustic motion, in KD
2
PO
4
crystals near the structural phase transition temperature T
c
. Photoelastic and electrooptic effects are observed to diverge near T
c
, suggesting applications in efficient light modulation and switching.