[23a-C202-1~5] 4.6 Terahertz Photonics

▲ [23a-C202-3] Carrier dynamics in semi-insulating and low-temperature-grown gallium arsenide photoconductive antenna devices under above-bandgap and below-bandgap photoexcitation

〇(PC)Alexander Escobar De Los Reyes¹, Jairrus Publico², Ivan Cedric Verona¹, John Paul Ferrolino², Vince Paul Juguilon¹, Lourdes Nicole Dela Rosa¹, Hannah Bardolaza¹, Neil Irvin Cabello¹, Elmer Estacio¹ (1.NIP, UP Diliman, 2.MSEP, UP Diliman)

Keywords:terahertz, photoconductive antenna

We study the THz emission properties of SI-GaAs and LT-GaAs at 1550 nm below-bandgap and 780 nm above-bandgap excitation conditions. We attribute the below-bandgap THz emission of SI-GaAs to the escape of trapped electrons in As precipitates and the THz emission of LT-GaAs to two-step photoabsorption due to midgap states. This work provide understanding on the dynamics and transport in GaAs-based PCA devices under below-bandgap photoexcitation.