Terahertz wave detection by heterodyne EO sampling using position sensitive detector
Abstract
We have recently reported a new electro-optic (EO) sampling scheme, the “heterodyne EO sampling,” where the EO sampling signal is detected as direct intensity changes in the probe beam without using any polarization optics. The heterodyne EO signal has a spatial distribution originating from the non-collinear phase-matching process: i) the signal polarity is reversed on the opposite half of the sampling beam cross section and ii) THz frequency components are detected angularly resolved in proportion to the frequency. Utilizing these spatial distribution characteristics of the heterodyne EOS signal, we proposed and demonstrated a detection method using Position Sensitive Detector (PSD). The results show that the heterodyne EOS using a PSD is a promising technique to extend the detection bandwidth.