Experimenting with Mesoscopic Systems

If one keeps accumulating atoms or molecules and binding them appropriately, when will the transition from atomic behavior to bulk state take place? Interestingly, as soon as a few of them get clustered, the system properties become quite distinct from either. Moreover, some of their physical characteristics vary immensely with size. The distinction is more pronounced when an intense laser field is applied on them. In the focus of the laser pulse, average particle density in a clustered gas can be very small, however, the local density of each cluster approaches that of a solid. This has huge repercussions on absorption of light and other properties of the resulting plasmas. Some of the fascinating features of such nanometric plasmas along with relevant measurement techniques will be presented in the talk.

Clusters, being ubiquitous in nature, offer more opportunities to tune the properties of matter at the nanoscale simply by producing composites of them, for example, upon doping. This introduces additional degrees of freedom like the ratio of the constituents and the spatial distribution of them. How such flexibilities can be exploited to couple more laser energy to the system and obtain fluxes of highly charged energetic ions on a table-top, will be discussed with particular emphasis on a newly developed methodology to microscopically image them.