title: Elemental fingerprinting of materials with sensitivity at the atomic limit.
abstract: By using synchrotron X-rays as a probe and a nanofabricated smart tip of a tunneling microscope as a detector, we have achieved chemical fingerprinting of individual nickel clusters on a Cu(111) surface at 2 nm lateral resolution, and at the ultimate single-atomic height sensitivity. Moreover, by varying the photon energy, we have succeeded to locally measure photoionization cross sections of just a single Ni nanocluster, which opens new exciting opportunities for chemical imaging of nanoscale materials.
authors.affiliation: Advanced Photon Source, Argonne National Laboratory , 9700 South Cass Ave, Argonne, Illinois 60439, United States.
authors.forename: Nozomi
authors.initials: N
authors.lastname: Shirato
authors.forename: Marvin
authors.initials: M
authors.lastname: Cummings
authors.forename: Heath
authors.initials: H
authors.lastname: Kersell
authors.forename: Yang
authors.initials: Y
authors.lastname: Li
authors.forename: Benjamin
authors.initials: B
authors.lastname: Stripe
authors.forename: Daniel
authors.initials: D
authors.lastname: Rosenmann
authors.forename: Saw-Wai
authors.initials: SW
authors.lastname: Hla
authors.forename: Volker
authors.initials: V
authors.lastname: Rose
keywords: X-ray microscopy; chemical imaging; scanning tunneling microscopy; smart tips; synchrotron