Open AccessTerahertz photoconductive waveguide emitter with excitation by a tilted optical pulse front
Author(s) -
Qamar Ul Islam,
Fanqi Meng,
Mark D. Thomson,
Hartmut G. Roskos
Publication year - 2020
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.403161
Subject(s) - terahertz radiation , optics , waveguide , tilt (camera) , optoelectronics , materials science , pulse (music) , common emitter , excitation , physics , mechanical engineering , quantum mechanics , detector , engineering
We explore the tilted-pulse-front excitation technique to control the superradiant emission of terahertz (THz) pulses from large-area photonconductive semiconductor switches. Two cases are studied. First, a photoconductive antenna emitting into free space, where the propagation direction of the optically generated THz beam is controlled by the choice of the tilt angle of the pump pulse front. Second, a THz waveguide structure with an integrated photoconductive window for the generation of THz radiation, where the injection of the THz radiation into a waveguide mode is optimized by the pulse front tilt. By providing long interaction lengths, such a waveguide-based optical-pump/THz-probe set-up may provide a new platform for the study of diverse short-lived optically induced excitations.