Ultrafast opto-mechanical terahertz modulators based on stretchable carbon nanotube thin films
Abstract
For terahertz (THz) wave applications, tunable and rapid modulation is highly required. When studied by means of optical pump-terahertz probe spectroscopy, single-walled carbon nanotubes (SWCNTs) thin films demonstrated ultrafast carrier recombination lifetimes with a high relative change in the signal under optical excitation, making them promising candidates for high-speed modulators. Here, combination of SWCNTthin films and stretchable substrates facilitated studies of the SWCNT mechanical properties under strain,and enabled the development of a new type of an opto-mechanical modulator. By applying a certain strain to the SWCNT films, the effective sheet conductance and therefore modulation depth can be fine-tuned to optimize the designed modulator. Modulators exhibited a photoconductivity change of 3-4 orders of magnitude under the strain due to the structural modification in the SWCNT network. Stretching was used to control the THz signal with a modulation depth of around 100 % without strain and 65 % at a high strainoperation of 40 %. The sensitivity of modulators to beam polarisation is also shown, which might also come in handy for the design of a stretchable polariser. Our results give a fundamental grounding for the design of high-sensitivity stretchable devices based on SWCNT films.
Keywords
Cite
@article{arxiv.2211.07312,
title = {Ultrafast opto-mechanical terahertz modulators based on stretchable carbon nanotube thin films},
author = {Maksim I. Paukov and Vladimir V. Starchenko and Dmitry V. Krasnikov and Gennady A. Komandin and Yuriy G. Gladush and Sergey S. Zhukov and Boris P. Gorshunov and Albert G. Nasibulin and Aleksey V. Arsenin and Valentyn S. Volkov and Maria G. Burdanova},
journal= {arXiv preprint arXiv:2211.07312},
year = {2022}
}