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Related Experiment Video

Updated: Jun 21, 2026

Characterization of Anisotropic Leaky Mode Modulators for Holovideo

Characterization of Anisotropic Leaky Mode Modulators for Holovideo

Published on: March 19, 2016

Design of high efficiency multi-GHz SiGe HBT electro-optic modulator.

Shengling Deng¹, Z Rena Huang, J F McDonald

¹Department of Electrical, Computer, and System Engineering, Rensselaer Polytechnic Institute, NY 12180, USA.

|August 6, 2009

Summary

This summary is machine-generated.

This study presents a silicon-germanium (SiGe) base heterojunction bipolar transistor (HBT) electro-optic modulator. The device demonstrates efficient phase shifting for optical communication applications.

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Transmission of Multiple Signals through an Optical Fiber Using Wavefront Shaping

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Transmission of Multiple Signals through an Optical Fiber Using Wavefront Shaping

Transmission of Multiple Signals through an Optical Fiber Using Wavefront Shaping

Published on: March 20, 2017

Area of Science:

Optoelectronics
Semiconductor Devices
Materials Science

Background:

Heterojunction bipolar transistors (HBTs) are key semiconductor devices.
Electro-optic (EO) modulators are crucial for optical communications.
Silicon-Germanium (SiGe) alloys offer tunable electronic and optical properties.

Purpose of the Study:

To design and analyze a novel HBT EO modulator.
To investigate the performance of a graded SiGe base for enhanced modulation.
To assess the device's potential for high-speed optical switching.

Main Methods:

Theoretical analysis of HBT device physics.
Modeling of EO modulation in a SiGe waveguide structure.
Simulation of optical propagation and phase shift characteristics.

Main Results:

A SiGe base HBT EO modulator was designed and analyzed.
A pi-phase shift was achieved with 74.5 microm interaction length for TM polarization at 1.55 microm wavelength.
The device exhibits a total optical attenuation of 3.9 dB and is expected to operate at 2.4 GHz.

Conclusions:

The proposed HBT EO modulator with a graded SiGe base shows promise for optical modulation.
The large waveguide cross-section facilitates fiber alignment.
The device's performance metrics suggest suitability for high-speed optical communication systems.