关于举行澳大利亚蒙纳士大学鲍桥梁副教授学术报告的通知

报告题目：Light matter interactions in 2D materials and device applications

报告人：鲍桥梁 副教授 （澳大利亚蒙纳士大学）

报告时间：2023年2月21日（周二）下午3:00-5:00

报告地点：北区国重502会议室

Abstract

Our research interests are mainly focused on optical characterization of 2D materials, more specifically, the light-matter interactions in the forms of nonlinear light absorption, light modulation (amplitude, phase and polarisation), photo-electrical conversion, wave-guiding and polaritonic manipulation. This talk will give an overview of photonic and optoelectronic device applications based on these optical phenomena in 2D materials. First, to overcome the limit light absorption in graphene and obtain large nonlinear optical modulation depth, we developed a serial of new saturable absorbers based on graphene heterostructures and other 2D materials, including graphene/Bi₂Te₃, black phosphorus and self-doped plasmonic 2D Cu_3-xP nanosheets as well as 2D halide perovskite. Second, in order to fabricate improved graphene photodetectors working in different spectral ranges, we integrated graphene with other 2D materials with variant electronic structures, for example, graphene/perovskite for visible light detection, graphene/MoTe₂ and graphene/black phosphorus for near infrared light detection, and graphene-Bi₂Te₃ for broadband infrared light detection. By fine tuning or aligning the electronic structure, we are able to engineer the photo-gating effect and depletion width in 2D material heterostructures, so as to achieve higher quantum efficiency and large photo-active area. Third, the THz light modulations associated with plasmonic excitation in graphene/Bi₂Te₃, topological insulator Bi₂Te₃, graphene nanoribbon and 3D graphene were investigated using both spectroscopic and real space imaging techniques. We developed a surface plasmon resonance (SPR) sensor using 2D antimonene nanosheets, and demonstrated 10,000 times improvement in sensitivity. Last, we update our recent progress on the observation of anisotropic and ultra-low-loss polariton propagation along the natural vdW material α-MoO₃. We will also present how the hyperbolic polaritons in α-MoO₃ thin slabs are delicately manipulated by controlling the interlayer twist angle. We experimentally observed tunable topological transitions from open (hyperbolic) to closed (elliptical) dispersion contours in twisted α-MoO3 bilayers at a photonic magic twist angle. We further demonstrated the manipulation and steering of the hyperbolic polaritons in this exotic material by chemical intercalation and edge orientation, an important step for building polaritonic circuitry. In summary, we have performed intensive researches on 2D materials integrated photonic and optoelectronic devices ranging from pulse lasers, waveguide, modulators to photodetectors, which are essential building blocks for constructing next generation integrated photonic circuitries and neuromorphic photonic processors.

References

[1]     Nature, 2018, 562: 557.

[2]     Nature, 2020, 582: 209.

[3]     Nature Commun., 2020,11: 2646.

[4]     Nature Commun., 2020,11: 6086.

[5]     Nature Rev. Phys., 2022, doi.org/10.1038/s42254-022-00472-0.

个人简介：

鲍桥梁于2007年博士毕业于武汉大学物理学院。2008年，在新加坡国立大学石墨烯研究中心从事博士后研究。2012年，受聘为苏州大学特聘教授。2016年被聘为澳大利亚蒙纳士大学终身副教授。研究兴趣主要集中于二维材料的光学特性以及其在光子学和光电器件中的应用。累计发表了230余篇文章，被引频次约40,000次，H指数为85。2018-2022连续5年入选科睿唯安（Clarivate Analytics）全球高被引用学者榜单。2009年国际上首次构筑石墨烯锁模超快光纤激光器。2011年首次构建了石墨烯宽波段光偏振器，相关研究发表于Nature Photonics。2018年实验上首次在天然范德华尔斯材料中观测到两种面内各向异性传播的超低损耗极化激元，相关研究发表于Nature，入选“2018中国光学十大进展”。 2020年发表在Nature上题为“扭转双层α-MoO3中的拓扑极化激元和光学魔角”的工作被英国皇家物理学会旗下Physics World网站评选为该年度“世界物理十大突破”。