报告人：Dr. Jianing Chen （CIC Nanogune, Spain）

Graphene holds great promise for ultra-compact and electronically controlled plasmonics. Recently, resonant coupling of propagating THz waves to plasmons in micro-ribbons has been demonstrated, while IR near-field microscopy has been applied to observe the coupling of graphene plasmons to phonons. In our work we use scattering-type scanning near-field optical microscopy (s-SNOM) to visualize propagating and localized infrared plasmon modes in graphene nanostructures in real space. By spectroscopic imaging we measure the graphene plasmon wavelength λ_p as a function of excitation wavelength, which confirms the theoretically predicted plasmon dispersion. We observe that the plasmon wavelength λ_p=λ₀/40 is remarkably reduced compared to the illumination wavelength λ₀, which can directly be attributed to the two-dimensionality and unique conductance properties of graphene. Furthermore, we demonstrate tunability of the plasmon wavelength by gating graphene nanoribbons on a SiO₂ substrate. The possibility to tune plasmons of extreme subwavelength electronically opens up a new paradigm in optical and opto-electronic telecommunications and information processing.

 

Jianing Chen obtained his PhD (on the topic of Tip-enhanced Raman Spectroscopy) under Prof. Hongxing Xu and Prof. Hongqi Xu at Dalian University of Technology and Institute of Physics, Beijing, CAS in 2008. After graduation he did postdoc in Department of Solid State Physics, Lund University, Sweden. In 2010 he went to Spain where he joined the group of Rainer Hillenbarand and Javier Aizpurua at the CSIC Center for Material Science and CIC Nanogune and worked on near-field optics. Currently, his research topics cover optical properties of optical antennas, IR antennas, graphene plasmonics and near-field spectroscopy. This work is done in collaboration with Frank Coppers and Javier Garcis de Abajo.

 

 

 

 

联系人：金奎娟 研究员（Tel：82648099）

 

主办单位：中国科学院光物理重点实验室