We report significant improvement in terahertz (THz) power and efficiency using photoconductive sources by use of a spatially extended line source excitation and the trap enhanced field effect that occurs in sources made on semi-insulating GaAs. The combination of high electric fields and reduced screening effects allows 10 µW of THz power to be generated with 14 mW of absorbed optical power, demonstrating nearly 0.1% optical-to-THz conversion efficiency.
© 2005 Optical Society of America
Joong H. Kim, Arup Polley, and Stephen E. Ralph, "Efficient photoconductive terahertz source using line excitation," Opt. Lett. 30, 2490-2492 (2005)