题 目：Optical properties of hybrid nanocrystal complexes

报告人：张伟 研究员

主持人：王鲁橹 讲师
时 间：周一（7月6日）15：00-16：30
地 点：主楼1214

报告人简介：

张伟，北京应用物理与计算数学研究所，研究员。1998年于中科院理论物理研究所获博士学位，1998至2000年在北京应用物理与计算数学研究所做博士后，2001至2007年间，先后于美国俄亥俄大学、肯塔基大学、印第安纳大学做博士后/研究学者，2007年8月至今，研究员，北京应用物理与计算数学研究所。

张伟在低维凝聚态/纳米体系的光学、电输运性质等方面做了系统的研究工作，在包括Nature， Angew. Chem. Int. Ed.，Nano Lett., J. Am. Chem. Soc.，Phys. Rev. Lett.等的国际核心期刊上发表SCI论文七十余篇，SCI引用千余次。曾获“于敏数理科学奖”，“中物院科技创新奖”。

报告简介：

Modern nanotechnology opens the possibility of combining nanocrystals of various materials with very different characteristics in one superstructure. Here we present semiclassical and complete quantum theories on the optical properties of hybrid molecules composed of semiconductor and metal nanoparticles. Excitons and plasmons in such a hybrid molecule become strongly coupled and demonstrate novel properties. At low incident light intensity, the exciton peak in the absorption spectrum is broadened and shifted due to incoherent and coherent interactions between metal and semiconductor nanoparticles. At high light intensity, the absorption spectrum demonstrates a surprising, strongly asymmetric shape. This shape originates from the coherent internanoparticle Coulomb interaction and can be viewed as a nonlinear Fano effect. The usual linear Fano effect is recovered in the weak field limit. We establish the relation between quantum and semiclassical theory.