Picosecond pulse scattering of highly-polarized electromagnetic wave measured by photoconductive sampling

The scaled-down electromagnetic scattering experiment based on the terahertz pulse generation and detection using dioramas has been suggested as one of the most promising applications of ultrafast photoconductive sampling. The electromagnetic pulse scattering, especially for the diffraction by conducting wedges and the reflection from planar surfaces in the scaled-down measurements is strongly sensitive to the polarization of the incident pulses. Moreover, the reflected pulse waveforms are distorted after the reflection and the diffraction depending on the polarization. We carefully examined the diffraction and the reflection phenomena of highly polarized picosecond pulses, based on the free-space terahertz photoconductive sampling. The changes of the temporal profile of the picosecond pulses diffracted from a slit on a thin copper plate and those reflected From a conducting cylinder of stainless steel were measured and discussed. Finally, the feasibility was proven by comparing the obtained pulse waveforms with the known solutions from the Maxwell equations and given boundary conditions.