Showing posts with label Songbai Li. Show all posts
Showing posts with label Songbai Li. Show all posts

Wednesday, May 15, 2019

Abstract-Multi-mode graphene based terahertz amplitude modulation enhanced by hollow cross H-structured metasurface


 

https://iopscience.iop.org/article/10.1088/1402-4896/ab1bfe/pdf

A graphene-metasurface based THz amplitude modulator enhanced with the hollow cross H array in a metal film is proposed. Based on the transmission line theory, the equivalent analysis model of the modulator is built. With the model, the multi-mode resonation excited by the metasurface is analyzed and the amplitude modulations of the THz transmission are discussed. By applying modulation voltage between the metallic metasurface and graphene film in the experiment, three enhanced modes in the transmission spectrum are observed and the maximum modulation depth is enhanced to 49.3% in the band of 0.1-1.8THz. The experimental results exhibit a good agreement with the theory analysis.

Monday, May 6, 2019

Abstract-Multi-mode graphene based terahertz amplitude modulation enhanced by hollow cross H-structured metasurface




Liangping Xia, Yixuan Zou, Man Zhang, Wenjuan Yan, Suihu Dang, Songbai Li, Shaoyun Yin,  Hongliang Cui

https://iopscience.iop.org/article/10.1088/1402-4896/ab1bfe/pdf

A graphene-metasurface based THz amplitude modulator enhanced with the hollow cross H array in a metal film is proposed. Based on the transmission line theory, the equivalent analysis model of the modulator is built. With the model, the multi-mode resonation excited by the metasurface is analyzed and the amplitude modulations of the THz transmission are discussed. By applying modulation voltage between the metallic metasurface and graphene film in the experiment, three enhanced modes in the transmission spectrum are observed and the maximum modulation depth is enhanced to 49.3% in the band of 0.1-1.8THz. The experimental results exhibit a good agreement with the theory analysis.

Monday, December 24, 2018

Abstract-Low loss terahertz devices based on polymer substrate


Liangping Xia, Hongyan Mao, Xinqun Zhang, Suihu Dang, Wenjuan Yan, Songbai Li,

https://www.spiedigitallibrary.org/conference-proceedings-of-spie/10848/1084808/Low-loss-terahertz-devices-based-on-polymer-substrate/10.1117/12.2505147.short?SSO=1


The fabrication method of hard template substrate supporting in the lithography process is proposed to realize THz devices based on low loss polymer substrate with large effective area. Based on this method, the THz polarizer with single layered and double layered grating structure are fabricated and measured. The transmission spectra indicates that the loss of the polarizer is low and the polarization extinction ratio is as high as 55dB and 70dB for single and double layered samples respectively. The THz band stop filter result indicates that the loss keeps low and the filter band width is wider for the multi-layered metallic structure.
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