报告题目：GaN-based Photodiodes for Visible Light Communication
主持人（邀请人）： 张立军 教授
摘要：Following the rapid development of GaN-based light emitting diodes (LEDs), visible light communication (VLC) has attracted considerable attention. Compared with traditional radio frequency wireless communication, VLC is more secure, without electromagnetic interference or license restriction. However, the optical modulation bandwidth of commercial light emitting diodes (LEDs) is only several tens of MHz. It is necessary to enhance the modulation bandwidth of LEDs significantly for VLC applications. In addition, the quantum efficiency (QE) and temporal response of the optical receiver in the VLC system are also important. Currently, Si-based photodetectors are used to detect blue light from white LEDs by implementing a blue-filtering technology. But this technology suffers from low light transmittance and complexity. Furthermore, the broadband response of Si-based photodetectors causes undesirable interference effects between the detected and background signals. GaN-based photodetectors could offer an alternative solution as they have a high band edge extinction ratio. However, the performance of InGaN visible light detectors is still not competitive with that of traditional Si-based detectors. Here, the progresses of the GaN-based photodiodes for visible light communication will be introduced. The works will lay a foundation to further enhance the performance of GaN-based photodiodes for light communication below 600 nm.
报告人简介：Prof. Lixia Zhao received the Ph. D degree in physics from University of Nottingham, UK, in 2005. Afterwards, she worked at the GaN research Center of University of Cambridge. From 2007 to 2009, she worked in the Forge Europa, UK and was responsible for the development and quality of semiconductor lighting. In 2009, she joined the Institute of semiconductor, CAS with the “Import Outstanding Technical Talent Program” from CAS and was elected as youth innovation member of CAS in 2011. She has authored or co-authored over 100 papers with more than 2100 citations, and applied over 30 patents. Currently her research interests are mainly focused on the physical properties of III-Nitride semiconductor optoelectronic devices.