Abstract

Electrons occupying surface states on the close-packed faces of noble metals form a two-dimensional (2-d) nearly free electron gas. Because this system is accessible to the scanning tunneling microscope (STM), it provides a unique opportunity to study the local properties of low-dimensional electrons. On Cu (111) we have observed standing wave patterns in the surface local density of states due to the quantum mechanical interference of surface state electrons scattering off of step edges and adsorbates. We find that Fe adatoms strongly scatter the surface state and, as a result, are good building blocks for constructing atomic-scale barriers (“quantum corrals”) to confine the surface state electrons. The barriers are constructed by individually positioning Fe adatoms using the tip of a cold (4 K) STM. Tunneling spectroscopy performed inside of the corrals reveals discrete resonances, consistent with size quantization. A more quantitative understanding is obtained by accounting for the multiple scattering of surface state electrons with the corrals’ constituent adatoms. This scattering is characterized by a complex phase shift which can be extracted from the electronic density pattern inside a quantum corral.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.