Self-balanced and self-phase-corrected electro-optic sampling in a birefringent crystal.

Mid-to-far-infrared (IR) spectral content is recorded using the novel self-balanced and self-phase-corrected electro-optical (EO) sampling arrangement. Self-balancing guarantees that the electric field emerging from the EO crystal yields a signal of zero via a Wollaston prism and balanced photodetector (i.e., without a wave plate following the EO crystal) in the absence of the electric field being sampled. Moreover, self-phase-correction ensures a nearly frequency-independent phase difference between the probe electric field pulse and the electric field pulse generated within the EO crystal via second-order nonlinear optical interactions. The self-balanced and self-phase corrected arrangement has the potential to yield enhancement of EO signals recorded using previously investigated birefringent crystals (implemented within traditional EO sampling geometries) and deliver optimum EO signal strengths when considering unexplored birefringent crystals.