AVS 47th International Symposium
    Processing at the Nanoscale/NANO 6 Thursday Sessions
       Session NS+NANO6+MC-ThA

Paper NS+NANO6+MC-ThA10
Development of a Photon Detection STM for Inelastic Light Emission

Thursday, October 5, 2000, 5:00 pm, Room 302

Session: Near-field Optics and Photonics
Presenter: D. Fujita, National Research Institute for Metals, Japan
Authors: D. Fujita, National Research Institute for Metals, Japan
W.-L. Deng, National Research Institute for Metals, Japan
T. Ohgi, National Research Institute for Metals, Japan
K. Ishige, National Research Institute for Metals, Japan
Correspondent: Click to Email
Recently it has been demonstrated that the light emission induced by tunneling electrons can be detected with normal STM operation even with atomic resolution. The possible processes are inelastic tunneling (IET) and hot-electron thermalization (HET). Generally speaking, in the case of IET, the tunneling electrons lose a part of the energy during the tunneling events to excite the state with some radiative decay processes. In the latter case, hot electrons lose the excess energy in the bulk. However, in order to get more detailed understanding of the luminescence process, much more precise measurements of these photons are required. For this purpose, we have developed a novel LT-UHV-STM system for the detection of light emission caused by the tunneling electrons. The emitted photons can be collected by the apex of a conductive and transparent optical fiber coated with a 100nm ITO (Indium-Tin-Oxide) film. Using a cooled photon detection system, single photon counting and spectroscopy with a very low noise level can be achieved. The system has been successfully applied to noble metal surfaces (Ag(111) and Cu(100)), and a direct-gap semiconductor surface (GaAs(110)) in UHV.