منابع مشابه
Distributed photomixers
Although the terahertz domain has been explored scientifically, components, especially sources, are needed to enable further exploration of the frequency range. A photomixer generates coherent THz radiation through optical heterodyne down-conversion. A terahertz-frequency beat signal on an optical carrier illuminates an ultrafast photoconductor, modulating the conductance. The time-varying cond...
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Low-temperature-grown (LTG) GaAs is used as an optical-heterodyne converter or photomixer, to generate coherent continuous-wave (CW) output radiation at frequencies up to 5 THz. Photomixers consist of an epitaxial LTG-GaAs layer that is patterned with interdigitated metal electrodes, on which two laser beams are focused with their frequencies offset by the desired difference frequency. The diff...
متن کاملGeneration and detection of coherent terahertz waves using two photomixers
A general technique has been demonstrated at microwave and submillimeter-wave frequencies for photoconductive sampling in the frequency domain using photomixers and continuous-wave laser diodes. A microwave version in which two photomixers were coupled by a transmission line was developed to quantitatively test the concept from 0.05 to 26.5 GHz. A quasioptical version using antenna-coupled phot...
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are not particularly noted for the pleasure which they give to their recipients. One meaning of the word dummy is a "counterfeit object." This seems to me the right word to describe a form of treatment which is intended to have no effect and I follow those who use it. A placebo is something which is intended to act through a psychological mechanism. It is an aid to therapeutic suggestion, but t...
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We prove that every recursively enumerable language can be generated by a programmed grammar with context-free core rules using unconditional transfer with leftmost derivation of type 3 or type 2. We show that every recursively enumerable tally language can be generated by a programmed grammar with context-free core rules using unconditional transfer or by some k-limited ET0L system, where k 2 ...
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ژورنال
عنوان ژورنال: Nature Photonics
سال: 2012
ISSN: 1749-4885,1749-4893
DOI: 10.1038/nphoton.2012.8