LiNbO3 TAPERED THz ANTENNA PARTIALLY FILLING THE METAL WAVEGUIDE
Abstract
Results on generation of ultrabroadband terahertz (THz) radiation in band 0.1-2 THz via optical rectification of femtosecond laser pulses in nonlinear tapered crystal are presented. It is shown that placing the LiNbO3 crystal in the free space and in the hollow waveguide both the time and spectral features of the emitted THz field are changed. Several intense spectral regions (at 279 GHz and 1 ТHz) whose frequency depends on the LiNbO3 size are observed. Excitation of ТHz radiation in the tapered nonlinear crystal antenna, partially filling the metal waveguide with the help of an optical femtosecond laser pulse permits the resolution of problems connected with input/output coupling – mode matching and single mode propagation.
About the Author
A. S. Nikoghosyan
Yerevan State University
Armenia
Armenia
PhD, Associate Professor, Department of Microwave Radiophysics
and Telecommunications
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Review
For citations:
Nikoghosyan A.S. LiNbO3 TAPERED THz ANTENNA PARTIALLY FILLING THE METAL WAVEGUIDE. Alternative Energy and Ecology (ISJAEE). 2015;(6):87-91. (In Russ.)
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