Tunneling spectroscopy on deposited silver clusters

• Applicant: Professor Dr. Karl-Heinz Meiwes-Broer
• Subject Area: Experimental Condensed Matter Physics
• Term: from 2003 to 2011
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5405640

With the advent of one-nanometer sized metallic structures in electronic component designs, quantum effects will increasingly play an important role. Along this line it becomes necessary to investigate and control the interaction between metal particles and clusters with a contact medium. The focus of this project will be on size-filtered silver particles and clusters deposited onto semi-conductor surfaces. In preliminary work we gained experience in studying surface-grown silver islands with the method of scanning tunneling spectroscopy. Ge(001) served as substrate under ultra-high vacuum conditions and at low temperatures. Whereas the resulting spectra are well structured and hint at pronounced quantum effects, the exact shape of the particles and the morphology at the contact area are principally not defined. In order to overcome this problem, we plan to deposit mass-filtered clusters. Addressing single clusters, occupied and unoccupied cluster states will be explored, thus yielding insight into the cluster size dependent electronic structure in the presence of a semi-conducting surface.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1153: Clusters at Surfaces: Electron Structure and Magnetism
• Participating Person: Dr. Ingo Barke