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Title: Detecting element specific electrons from a single cobalt nanocluster with synchrotron x-ray scanning tunneling microscopy

Abstract

Here, we use a nanofabricated scanning tunneling microscope tip as a detector to investigate local X-ray induced tunneling and electron emission from a single cobalt nanocluster on a Au(111) surface. The tip-detector is positioned a few angstroms above the nanocluster, and ramping the incident X-ray energy across the Co photoabsorption K-edge enables the detection of element specific electrons. Atomic-scale spatial dependent changes in the X-ray absorption cross section are directly measured by taking the X-ray induced current as a function of X-ray energy. From the measured sample and tip currents, element specific X-ray induced current components can be separated and thereby the corresponding yields for the X-ray induced processes of the single cobalt nanocluster can be determined. The detection of element specific synchrotron X-ray induced electrons of a single nanocluster opens a new avenue for materials characterization on a one particle at-a-time basis.

Authors:
 [1];  [2];  [2];  [1];  [2];  [2];  [1];  [2]
  1. Argonne National Lab. (ANL), Argonne, IL (United States); Ohio Univ., Athens, OH (United States)
  2. Argonne National Lab. (ANL), Argonne, IL (United States)
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22). Scientific User Facilities Division
OSTI Identifier:
1416532
Grant/Contract Number:
AC02-06CH11357; FG02-02ER46012; SC70705
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Applied Physics Letters
Additional Journal Information:
Journal Volume: 111; Journal Issue: 10; Journal ID: ISSN 0003-6951
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; 36 MATERIALS SCIENCE; photoemission

Citation Formats

Kersell, Heath, Shirato, Nozomi, Cummings, Marvin, Chang, Hao, Miller, Dean, Rosenmann, Daniel, Hla, Saw -Wai, and Rose, Volker. Detecting element specific electrons from a single cobalt nanocluster with synchrotron x-ray scanning tunneling microscopy. United States: N. p., 2017. Web. doi:10.1063/1.4990818.
Kersell, Heath, Shirato, Nozomi, Cummings, Marvin, Chang, Hao, Miller, Dean, Rosenmann, Daniel, Hla, Saw -Wai, & Rose, Volker. Detecting element specific electrons from a single cobalt nanocluster with synchrotron x-ray scanning tunneling microscopy. United States. doi:10.1063/1.4990818.
Kersell, Heath, Shirato, Nozomi, Cummings, Marvin, Chang, Hao, Miller, Dean, Rosenmann, Daniel, Hla, Saw -Wai, and Rose, Volker. 2017. "Detecting element specific electrons from a single cobalt nanocluster with synchrotron x-ray scanning tunneling microscopy". United States. doi:10.1063/1.4990818. https://www.osti.gov/servlets/purl/1416532.
@article{osti_1416532,
title = {Detecting element specific electrons from a single cobalt nanocluster with synchrotron x-ray scanning tunneling microscopy},
author = {Kersell, Heath and Shirato, Nozomi and Cummings, Marvin and Chang, Hao and Miller, Dean and Rosenmann, Daniel and Hla, Saw -Wai and Rose, Volker},
abstractNote = {Here, we use a nanofabricated scanning tunneling microscope tip as a detector to investigate local X-ray induced tunneling and electron emission from a single cobalt nanocluster on a Au(111) surface. The tip-detector is positioned a few angstroms above the nanocluster, and ramping the incident X-ray energy across the Co photoabsorption K-edge enables the detection of element specific electrons. Atomic-scale spatial dependent changes in the X-ray absorption cross section are directly measured by taking the X-ray induced current as a function of X-ray energy. From the measured sample and tip currents, element specific X-ray induced current components can be separated and thereby the corresponding yields for the X-ray induced processes of the single cobalt nanocluster can be determined. The detection of element specific synchrotron X-ray induced electrons of a single nanocluster opens a new avenue for materials characterization on a one particle at-a-time basis.},
doi = {10.1063/1.4990818},
journal = {Applied Physics Letters},
number = 10,
volume = 111,
place = {United States},
year = 2017,
month = 9
}

Journal Article:
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  • We use a nanofabricated scanning tunneling microscope tip as a detector to investigate local X-ray induced tunneling and electron emission from a single cobalt nanocluster on a Au(111) surface. The tip-detector is positioned a few angstroms above the nanocluster, and ramping the incident X-ray energy across the Co photoabsorption K-edge enables the detection of element specific electrons. Atomic-scale spatial dependent changes in the X-ray absorption cross section are directly measured by taking the X-ray induced current as a function of X-ray energy. From the measured sample and tip currents, element specific X-ray induced current components can be separated and therebymore » the corresponding yields for the X-ray induced processes of the single cobalt nanocluster can be determined. The detection of element specific synchrotron X-ray induced electrons of a single nanocluster opens a new avenue for materials characterization on a one particle at-a-time basis.« less
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