Two-fold improvement of THz optoelectronic generation and detection

Summary form only given. In the ultrafast optoelectronic community, different techniques of generation and detection of free-space terahertz pulses have been developed during the last few years. One of these techniques is the use of ZnTe crystals, with a femtosecond Ti:sapphire laser, to generate THz beam (optical rectification) and to detect the THz beam (Pockels effect). The rectified generation and electro-optic detection greatly improve the frequency bandwidth of the THz beam. We have applied the polarization modulation technique for optoelectronic generation and detection of a THz beam. Compared with the conventional amplitude modulation with a lock-in amplifier, the optical polarization modulation provides a two-fold increase of the dynamic range. We demonstrated significant improvement for the electro-optic THz imaging.