A number of transverse stratified configurations of metal and dielectric layers are studied for modulating Terahertz radiation in amplitude and phase. Pass band flat-top response and high wide-band transmission is achieved by means of a metallic grating filled with Liquid Crystal (LC) in different configurations and with the use of either grazing angles of incidence or cuts pierced within the grating. The transverse configuration with thin LC films allows for high speed tunability with low applied voltage. A dielectric grating with non-continuous electrodes is studied showing wide pass band response suitable for phase modulation applications.
Daniele Lo Forti,
Robert G. Lindquist,
Martin S. Heimbeck,
"Tunable Amplitude and Phase Modulation in Terahertz Regime Using Transverse Stratified Configuration," Progress In Electromagnetics Research,
Vol. 150, 59-71, 2015. doi:10.2528/PIER14092002
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