时间：2017年4月24日上午10：00

地点：主楼C2-401会议室

报告人：Dr. Markus Raschke

报告题目：Optical antenna based nano-focused multimodal imaging: new ultra-high spatial resolution microscopies for materials research

Abstract：

To understand and ultimately control the properties of most functional materials, from molecular soft-matter to quantum materials, requires access to the structure, coupling, and dynamics on the elementary time and length scales that define the microscopic interactions in these materials. To gain the desired nanometer spatial resolution with simultaneous spectroscopic specificity we combine scanning probe microscopy with different optical, including coherent, nonlinear, and ultrafast spectroscopies. The underlying near-field interaction mediated by the atomic-force or scanning tunneling microscope tip provides the desired deep-sub wavelength nano-focusing enabling few-nm spatial resolution. I will introduce our generalization of the approach in terms of the near-field impedance matching to a quantum system based on special optical antenna-tip designs. The resulting enhanced and qualitatively new forms of light-matter interaction enable measurements of quantum dynamics in an interacting environment or to image the electromagnetic local density of states of thermal radiation. Other applications include the inter-molecular coupling and dynamics in soft-matter hetero-structures, surface plasmon/phonon interferometry as a probe of electronic structure and dynamics in 2D materials, and quantum phase transitions in correlated electron materials. These examples highlight the general applicability of the new near-field microscopy approach, complementing emergent X-ray and electron imaging tools, aiming towards the ultimate goal of probing matter on its most elementary spatio-temporal level. 

个人简介

Dr. Markus Raschke, 美国科罗拉多大学博尔德分校物理系教授，美国科学促进会（AAAS）Fellow、美国物理学会（APS）Fellow、美国光学学会（OSA）Fellow。Markus Raschke博士于1999年毕业于德国马克思•普朗克量子光学研究所，获得博士学位。于1999年至2006年分别在美国加州大学伯克利分校、德国洪堡大学和德国马克思•波尔研究所从事博士后工作。于2006年至2010年在美国华盛顿大学升任至副教授，并于2010年至今在科罗拉多大学博尔德分校任教授。

Markus Raschke博士主要从事应用于光学成像和精密测量的拥有纳米级空间分辨率和飞秒级时间分辨率的线性/非线性/超快近场光学方面的研究，其是该领域国际公认的顶尖科学家。Markus Raschke博士在Nature、Nature Nanotechnology、Nature Photonics、Nature Communications、Advanced Materials、Physical Review Letters、PNAS、JACS、Nano Letter等顶级期刊上发表论文100余篇，其Google引用高达4720次（H指数37），并取得4项美国专利。