Spatial Pattern Formation of Optically Excited Carriers in Photoconductive THz Antennas
Abstract
We have investigated the role of spatio-temporal carrier dynamics in photoconductive THz antennas. To this end, the photoluminescence from a GaAs/AlGaAs quantum well has been spatially resolved after femtosecond laser excitation for different electric bias fields applied in the plane of the well. The photoluminescence patterns demonstrate substantially different electron-hole dynamics across the excitation laser spot. The density dependence of screening combines with the lateral variation of the carrier density to produce the observed effects. The experimental data are compared to a self-consistent calculation of the drift-diffusion equation for electrons and holes and Poisson's equation for the electric field in both space and time. Our results prove that the spatial variation of the carrier dynamics should be taken into account for further optimization of THz antennas.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 29, 2000
- Accession Number
- ADP011796
Entities
People
- G. Hein
- K. Pierz
- M. Bieler
- M. Koch
- U. Siegner