Design of high extinction ratio silicon electro optic modulator based on coupled hybrid plasmonic waveguide using graphene

The electro-optic modulator is a very important device in silicon photonics, which is responsible for the conversion of optical signals and electrical signals. For the electro-optic modulator, the carrier density of waveguide region is one of the key parameters. The traditional method of increasing carrier density is to increase the external modulation voltage, but this way will increase the modulation loss and also is not conducive to photonics integration. This paper presents a micro-nano Si/SiGe/Si double heterojunction electro-optic modulation structure. Based on the band theory of single heterojunction, the barrier heights are quantitatively calculated, and the carrier concentrations of heterojunction barrier are analyzed. The band and carrier injection characteristics of the double heterostructure structure are simulated, respectively, and the correctness of the theoretical analysis is demonstrated. The micro-nano Si/SiGe/Si double heterojunction electro-optic modulation is designed and tested, and comparison of testing results between the micro-nano Si/SiGe/Si double heterojunction micro-ring electro-optic modulation and the micro-nano Silicon-On-Insulator (SOI) micro-ring electro-optic modulation, Free Spectrum Range, 3 dB Bandwidth, Q value, extinction ratio, and other parameters of the micro-nano Si/SiGe/Si double heterojunction micro-ring electro-optic modulation are better than others, and the modulation voltage and the modulation loss are lower.

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Active Manipulation of the Spin and Orbital Angular Momentums in a Terahertz Graphene-Based Hybrid Plasmonic Waveguide

Nanomaterials ◽

10.3390/nano10122436 ◽

2020 ◽

Vol 10 (12) ◽

pp. 2436

Author(s):

Ziang Wang ◽

Qilong Tan ◽

Yong Liang ◽

Xia Zhou ◽

Wen Zhou ◽

...

Keyword(s):

Integrated Circuits ◽

Quantum Information Processing ◽

Extinction Ratio ◽

Transverse Component ◽

Phase Delay ◽

Plasmonic Waveguide ◽

Polarization Angle ◽

Multiple Functions ◽

Hybrid Plasmonic Waveguide ◽

Polarization Filtering

Angular momentums (AMs) of photons are crucial physical properties exploited in many fields such as optical communication, optical imaging, and quantum information processing. However, the active manipulation (generation, switching, and conversion) of AMs of light on a photonic chip remains a challenge. Here, we propose and numerically demonstrate a reconfigurable graphene-based hybrid plasmonic waveguide (GHPW) with multiple functions for on-chip AMs manipulation. Its physical mechanism lies in creating a switchable phase delay of ±π/2 between the two orthogonal and decomposed linear-polarized waveguide modes and the spin-orbit coupling in the GHPW. For the linear-polarized input light with a fixed polarization angle of 45°, we can simultaneously switch the chirality (with −ħ/+ħ) of the transverse component and the spirality (topological charge ℓ = −1/+1) of the longitudinal component of the output terahertz (THz) light. With a switchable phase delay of ±π in the GHPW, we also developed the function of simultaneous conversion of the charity and spirality for the circular-polarized input light. In addition, a selective linear polarization filtering with a high extinction ratio can be realized. With the above multiple functions, our proposed GHPWs are a promising platform in AMs generation, switching, conversion, and polarization filtering, which will greatly expand its applications in the THz photonic integrated circuits.

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Multi-Parameter Optimization of an InP Electro-Optic Modulator

Symmetry ◽

10.3390/sym12111920 ◽

2020 ◽

Vol 12 (11) ◽

pp. 1920

Author(s):

Mikhail Stepanenko ◽

Igor Yunusov ◽

Vadim Arykov ◽

Pavel Troyan ◽

Yury Zhidik

Keyword(s):

Extinction Ratio ◽

Optical Loss ◽

Optimization Method ◽

Optical Signal ◽

Optical Parameters ◽

Electro Optic ◽

Starting Point ◽

Input Parameters ◽

Optical Paths ◽

Electro Optic Modulator

In this article, a method for indium phosphide (InP) electro-optic modulator (EOM) optimization is introduced. The method can be used for the design and analysis of an EOM based on the Mach-Zehnder interferometer (MZI) design. This design is based on the division of the input optical signal into two optical paths and then, after processing, it combines the light into a single waveguide. The symmetry of the structure can provide state-of-the-art EOM characteristics with a push-pull control signal. Using a traveling wave electrode (TWE) design as a starting point, the authors varied the heterostructure design and optical waveguide parameters to obtain the optimal values of initial optical loss, evenness of the initial optical loss in the operating wavelength range, and the extinction ratio and length of the modulator arm. The key features of the proposed optimization method include the following: all independent input parameters are linked into a single system, where the relationship between the electrical and optical parameters of the modulator is realized; all physically realizable combinations of the input parameters are available for analysis; and EOM optimization is possible for one target parameter or for a group of target parameters. The results of the EOM optimization using the described method are presented.

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New double V-groove plasmonic waveguide for electro-optic modulator

IET Optoelectronics ◽

10.1049/iet-opt.2017.0029 ◽

2017 ◽

Vol 11 (6) ◽

pp. 278-284 ◽

Cited By ~ 1

Author(s):

Mohsen Salehi ◽

Nosrat Granpayeh

Keyword(s):

Plasmonic Waveguide ◽

Electro Optic ◽

Electro Optic Modulator

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An Electro-Optic Modulator Bias Point Stabilization Technique for the Distributed Brillouin Sensing System

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.71-78.1200 ◽

2011 ◽

Vol 71-78 ◽

pp. 1200-1203

Author(s):

Kai Zhang ◽

Yi Xin Zhang

Keyword(s):

Digital Signal Processor ◽

Extinction Ratio ◽

Digital Signal ◽

External Factors ◽

Sensing System ◽

Electro Optic ◽

Variable Bias ◽

Stabilization Technique ◽

Bias Point ◽

Electro Optic Modulator

During the measurement of a BOTDR system, it is significant to keep the extinction ratio of probe pulse uniform if constant sensing performance is desired. However the bias point of an electro-optic modulator (EOM) may slowly changes due to many external factors. Thus the variable bias point of the EOM must be stabilized. In this paper, a novel and simplified stabilization technique based on digital signal processor and step-by-step tracking algorithm is proposed. Contrast experiments with and without the stabilization are performed. The experimental results show that our method can lock the EOM’s bias point quite well and improve the sensing system’s performance obviously.

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