Terahertz induced nonlinear effects in doped Silicon observed by open-aperture Z-scan

We demonstrate the field dependent transmission of intense Terahertz (THz) pulses in doped Silicon. The strong interaction of charge carriers with the intense THz pulses leads to intervalley scattering of electrons within the conduction band. The change in the mobilities in the different valleys leads to 18% enhancement in the transmission through the sample at the peak THz electric fields of 135 kV/cm.