Open AccessActive bidirectional electrically-controlled terahertz device based on dimethyl sulfoxide-doped PEDOT:PSS
Author(s) -
Wei Wang,
Hongyu Ji,
Dandan Liu,
Luyao Xiong,
Yanbing Hou,
Bo Zhang,
Jingling Shen
Publication year - 2018
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.26.025849
Subject(s) - materials science , terahertz radiation , pedot:pss , optoelectronics , modulation (music) , doping , amplitude modulation , silicon , optics , frequency modulation , radio frequency , layer (electronics) , nanotechnology , electrical engineering , physics , engineering , acoustics
A high-efficiency active bidirectional electrically-controlled terahertz device based on DMSO-doped PEDOT:PSS with low-power photoexcitation is investigated. Under low-power optical excitation of 30 mW (0.5 W/cm 2 ) and under bias voltages ranging from -0.6 V to 0.5 V, spectrally broadband modulation of THz transmission over a range from -54% to 60% is obtained over the frequency range from 0.2 to 2.6 THz in a MEH-PPV/PEDOT:PSS:DMSO/Si/PEDOT:PSS:DMSO hybrid structure. By considering the combined carrier density characteristics of the proposed device, it is found that the large-scale amplitude modulation can be ascribed to the electrically-controlled carrier density in the silicon layer with the assistance of the p-n junction that consists of the DMSO-doped PEDOT:PSS and silicon. Bidirectional modulation has a larger modulation range and is easier to use in communications applications when compared with unidirectional modulation. These results show great potential for application to the design of active broadband terahertz devices.