High Field Terahertz Time-Domain Spectroscopy of Lactose Monohydrate

High field terahertz spectroscopy measurements of lactose monohydrate are presented. It is found that the feature at 0.53 THz, relating to the translatory motion of the lactose molecules along the long axis of the unit cell, becomes saturated with an incident THz field strength of 26 kV/cm for a pure powdered lactose sample. We also obtain an estimate of the feature at 1.37 THz to become saturated with a THz field strength of 205 kV/cm. This nonlinear saturation indicates the potential of dynamically distorting the crystal structure at sufficiently high fields.