题　目：Epitaxial graphene for photonics and optoelectronics

报告人：季伟 教授 （新加坡国立大学）

时　间：3月31日（周六），上午10：00

地　点：物理馆512会议室

Abstract: 
Since the discovery of exfoliated graphene in 2004, it has been in the exclusive domain of condensed-matter physicists for understanding its unique electronic and optical properties and of material scientists for syntheses of high-quality, large-scale and cost-effective graphene. Now, research focus has been shifted towards exploring its applications in electronic devices due to its excellent material properties, such as high electronic mobility, optical transparency, and other quantum-mechanical properties. As a potential material in photonics and optoelectronics, graphene has also been demonstrated by several recent results, ranging from solar cells and light-emitting devices to touch screens, photodetectors and ultrafast lasers. For in-depth review, readers are referred to Ref. [1]. Here, we present our demonstration of epitaxial graphene for photonic and optoelectronic devices, in particular, for both two-photon absorbers [2] and large-area, efficient photodetectors [3,4]。

Reference:

[1] Graphene photonics and optoelectronics, Bonaccorso F, Sun Z, Hasan T and Ferrari AC, Nature Photonics 4, 611 (2010).
[2] Giant two-photon absorption in bilayer graphene, Yang H, Feng X, Wang Q, Huang H, Chen W, Wee ATS, Ji W, Nano  Letters 11, 2622 (2011). 
[3] Laser patterning of epitaxial graphene for Schottky junction photodetectors, Singh RS, Nalla V, Chen W, Wee ATS, Ji W, ACS Nano 5, 5969 (2011).
[4] Photoresponse in epitaxial graphene with asymmetric metal contacts, Sing RS, Nalla V, Chen W, Ji W, Wee ATS, Appl Phys Lett 100, 093116 (2012).

Biography of Wei Ji

1978-1982: Fudan University, Shanghai, China, B,Sc in Physics.
1983-1990: Heriot-Watt University, Edinburgh, Scotland UK, M.Sc in 
                 Optoelectronics, PhD in Physics, and Research Associate.
1991-date:  National University of Singapore, Singapore, Lecturer, Associate  Professor, Full Professor and Vice Dean of  Science Faculty.

During the above period, as a visiting scholar, he spent 2~5 months, respectively, in University of Tokyo, Japan; Rensselaer Polytechnic Institute, Troy, NY; and Center for Research and Education in Optics and Lasers, University of  Central Florida, FL. Since 2011, he has been appointed as Associate Editor forOptical Materials Express. He co-authored 200 or so research papers with an h-index of 39.