Optical spatio-temporal optical control of electron-induced processes at graphene-supported metal cluster nano-structures

石墨烯支撑金属簇纳米结构电子诱导过程的光学时空光学控制

• 批准号: 138792705
• 负责人: Professor Dr. Thorsten M. Bernhardt
• 金额: --
• 依托单位: Institut für Oberflächenchemie und Katalyse
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2009
• 资助国家: 德国
• 起止时间: 2008-12-31 至 2011-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/138792705?language=en
• 关键词: Optical; spatio; temporal; optical; control; Optical; spatio; temporal; optical; control

In this proposal we wish to explore the potential of optimal control with shaped ultrafast laser pulses to localize the electromagnetic field in metal nano-cluster arrays consisting of graphene-supported size-selected silver clusters with extensions from a few atoms to the nanometer scale. Nothing is known so far about the optical properties of such arrays and we expect to find interesting new phenomena in particular also because of the intriguing electronic propensities of the 2D-material graphene. Graphene is employed as a substrate to provide a geometric template, i.e., to define the cluster distances – its potential to also provide electronic coupling between the clusters will be a subject of investigation. Size-selected clusters will be employed to obtain perfectly monodisperse samples and to investigate the effect of the transition from discrete to plasmonic electronic cluster structure on the possibility of field localization. Optical excitation will be provided by modulated (frequency, phase, polarization) ultrafast laser pulses. In a new experimental approach, the effect of the electromagnetic field localization will be probed by detecting the effectiveness of the electron-emission-induced dissociation of physisorbed adsorbate molecules (CH3Br, CH3Cl) on the metal clusters. Thus, the molecular fragment (CH3) mass signal will be employed as feedback signal in the control loop to obtain the optimal electromagnetic field. The investigation of the field localization will be performed by scanning tunnelling microscopic detection of the spatial extent of the metal cluster halogenation as a function of the parameters cluster size and cluster separation.

在此提案中，我们希望通过形状的超快激光脉冲来探索最佳控制的潜力，以将电子场定位在金属纳米簇阵列中，这些阵列由石墨烯支持的尺寸选择的银簇组成，并从几个原子延伸到纳米计尺度。到目前为止，关于此类阵列的光学性质迄今为止尚无众所周知，我们希望发现有趣的新现象，因为2D材料石墨烯具有有趣的电子特性。石墨烯是作为基板提供几何模板的基板，即定义群集距离 - 其在簇之间提供电子耦合的潜力将是投资的主题。将进行大小选择的簇以获取完美的单分散样品，并研究从离散到塑料电子群集结构的过渡对场定位的可能性的过渡。光学兴奋将通过调制（频率，相，极化）超快激光脉冲提供。在一种新的实验方法中，将通过检测物质诱导的物理吸附吸附物分子（CH3BR，CH3CL）对金属簇的分离的有效性来探测电子场定位的效果。这是在控制回路中用作反馈信号的分子片段（CH3）质量信号，以获得最佳的电磁场。通过扫描金属簇卤化的空间范围，将进行现场定位的投资，这是参数群集大小和群集分离的函数。