Toward a 1550 nm InGaAs photoconductive switch for terahertz generation

摘要

We report a terahertz (THz) photoconductive switch made from a composite of metal ErAs nanoparticles embedded in In_(0.53)Ga_(0.47)As and coupled to a square spiral antenna. The THz output power was measured in a 77 K cryostat by using a standard hyperhemisphere-lens package, a Golay cell outside the cryostat, and a quasi-optical filter bank for spot frequency spectral measurements. Results indicate an average output power of approx12 (mu)W at 22 V bias using 140 mW of optical pump power from a subpicosecond fiber mode-locked laser. In addition, the THz spectra displayed invariance to bias voltage despite operating near impact ionization.