Epitaxial stresses in an InGaAs photoconductive layer for terahertz antennas

The effect of epitaxial stresses on the excess-carrier dynamics and the terahertz radiation spectrum of the In$_{y}$Ga$_{1-y}$As films have been investigated by optical pump-probe and terahertz time-domain spectroscopy. It has been demonstrated that a In$_{y}$Ga$_{1-y}$As film with a higher mechanical stress has the shorter excesscarrier lifetime and broader terahertz radiation spectrum.