Open AccessHigh‐modulation depth modulator based on double‐layer graphene with a low bias voltage
Author(s) -
Dapeng Zhou,
Binggang Xiao,
Lihua Xiao,
Fenglei Guo,
Xiumin Wang
Publication year - 2019
Publication title -
micro and nano letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.25
H-Index - 31
ISSN - 1750-0443
DOI - 10.1049/mnl.2018.5511
Subject(s) - graphene , modulation (music) , materials science , broadband , electro optic modulator , bandwidth (computing) , biasing , optoelectronics , optical modulator , amplitude modulation , voltage , frequency modulation , electronic engineering , optics , computer science , telecommunications , nanotechnology , phase modulation , physics , electrical engineering , acoustics , engineering , phase noise
An efficient modulation can be obtained by graphene due to its outstanding light‐matter interaction, and many kinds of modulators based on graphene have been studied during the last couple of years. However, there still exist unsolved issues in graphene‐based modulators, such as how to make a balance between modulation depth and modulation bandwidth. This work proposes a reflective modulator with relatively high‐modulation depth and wide working bandwidth. The proposed modulator has a simple five‐layered structure of graphene–silica–graphene–silicon‐metal. They use an effective method of finite element method to simulate the performance of this modulator, and obtain a modulation depth of 96% with a low bias voltage of ∼4 V. Furthermore, they calculate the modulation speed by the equivalent circuit method, and obtain the maximum modulation speed of about 25 kHz and a wide broadband of 72 kHz from theoretical analysis. Therefore, this high‐performance modulator provides an effective method for terahertz communication devices.