Title :
Optimization of photomixers and antennas for continuous-wave terahertz emission
Author :
Gregory, Ian S. ; Baker, Colin ; Tribe, William R. ; Bradley, Ian V. ; Evans, Michael J. ; Linfield, Edmund H. ; Davies, Giles ; Missous, Mohamed
Author_Institution :
Cavendish Lab., Univ. of Cambridge, UK
fDate :
5/1/2005 12:00:00 AM
Abstract :
We have studied terahertz emission from interdigitated finger photomixers coupled to planar antenna structures. Using both pulsed and continuous-wave excitation, polarization measurements reveal that the antenna design dominates the properties of the radiated output at frequencies below 0.6 THz, while the efficiency at higher frequencies is additionally dependent on the design of the photomixer fingers. We have produced terahertz maps of the device, characterizing the photomixer by measuring the generated power as a function of the excitation position. Together, these measurements have allowed us to understand better the distinct roles of the photomixer and antenna in emission at different frequencies and, hence, independently optimize these components.
Keywords :
microwave photonics; photoconducting devices; submillimetre wave antennas; submillimetre wave mixers; submillimetre waves; continuous-wave terahertz emission; photomixers; planar antennas; Antenna measurements; Character generation; Fingers; Frequency measurement; Planar arrays; Polarization; Position measurement; Power measurement; Pulse measurements; Submillimeter wave measurements; Continuous-wave (CW); LT-GaAs; photoconductive antenna; photomixer; terahertz;
Journal_Title :
Quantum Electronics, IEEE Journal of
DOI :
10.1109/JQE.2005.844471