Title :
THz photomixing employing travelling-wave photodetectors
Author :
Stöhr, Andreas ; Malcoci, Andrei ; Jäger, Dieter
Author_Institution :
Univ. Duisburg-Essen, Duisburg, Germany
Abstract :
This paper reports on recent advances n the optical generation of continuous-wave THz signal by photomixing in ultra high-frequency 1.55μm travelling-wave photodetectors (TWPD). We discuss the fundamental physical effects determining the frequency dependent quantum efficiency and saturation output current of TWPD. An extended equivalent circuit for a TWPD is presented covering electrical wave propagation effects at frequencies above 1 THz. The power penalty in TWPD due to velocity mismatch is theoretically investigated. Experimentally, ultra-wideband (0.06-1 THz) optical heterodyne photomixing employing a 1.55μm TWPD coupled to a rectangular WR10 waveguide is presented as well as photonic emitter modules employing TWPDs integrated with planar antenna structures.
Keywords :
electromagnetic wave propagation; equivalent circuits; millimetre wave generation; photodetectors; planar antenna arrays; rectangular waveguides; 0.06 to 1 THz; 1.55 microns; THz photomixing; continuous-wave THz signal; electrical wave propagation; equivalent circuit; frequency dependent quantum efficiency; microwave photonics; millimeter wave generation; millimeter wave imaging; optical generation; optical heterodyne photomixing; photonic emitter modules; physical effects; planar antenna structures; rectangular WR10 waveguide; saturation output current; travelling-wave photodetectors; velocity mismatch; Equivalent circuits; Frequency dependence; Integrated optics; Optical mixing; Optical propagation; Optical saturation; Photodetectors; Signal generators; Stimulated emission; Ultra wideband technology;
Conference_Titel :
Microwave Symposium Digest, 2004 IEEE MTT-S International
Print_ISBN :
0-7803-8331-1
DOI :
10.1109/MWSYM.2004.1335867
