Abstract:
The authors demonstrate an efficient room temperature source of terahertz radiation using
femtosecond laser pulses as a pump and GaAs structures with periodically inverted crystalline
orientation, such as diffusion-bonded stacked GaAs and epitaxially grown orientation-patterned
GaAs, as a nonlinear optical medium. By changing the GaAs orientation-reversal period
(504–1277 μm), or the pump wavelength (2–4.4 μm), we were able to generate narrow-bandwidth
(~100 GHz) terahertz wave packets, tunable between 0.9 and 3 THz, with the optical-to-terahertz
photon conversion efficiency of 3.3%.
