Transmission of Slow Highly Charged Ions Through Ultra-thin Carbon Nano-sheets

Abstract

Transmission properties of slow highly charged ions through nanometer thick foils are discussed. We also report on the measurement of the energy loss and the charge states of 46.2 keV Ne10+-ions and 11.7 keV Ne3+-ions transmitted through ultra-thin carbon nano-sheets. The sheets had a thickness of 1.2 nm (single molecular layer) and 3.6 nm (three molecular layers). The measured energy loss of the transmitted ions is considerably smaller than the calculated energy loss by SRIM but it is in agreement with energy loss calculated using the Firsov model. The majority of the transmitted ions retain their initial charge state (up-to 98 %) contrary to prediction by the classical over-the-barrier model. The results suggest that the energy loss of slow highly charged ions in such thin sheets is only due to the electronic excitations, without charge exchange inside the target.