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An adjustable oxide-free tunnel junction for vibrational spectroscopy of molecules

Appl. Phys. Lett. 75, 2500 (1999); doi:10.1063/1.125061

Issue Date: 18 October 1999

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Darin T. Zimmerman
Department of Physics, Penn State Altoona College, Altoona, Pennsylvania 16601-3760

Michael B. Weimer and Glenn Agnolet
Department of Physics, Texas A&M University, College Station, Texas 77843-4242
We describe an adjustable, oxide-free, tunnel junction with the stability necessary to observe the vibrational modes of molecules adsorbed on clean metal surfaces. We illustrate the capabilities of this device with inelastic tunneling data from junctions whose barriers are formed by neon/acetylene mixtures of varying concentration. From the concentration dependence of the inelastic spectra, we can distinguish between acetylene molecules chemisorbed on the metal electrodes and those that are either physisorbed or incorporated in the neon barrier. ©1999 American Institute of Physics.
History: Received 14 June 1999; accepted 23 August 1999
Permalink: http://link.aip.org/link/?APPLAB/75/2500/1
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KEYWORDS and PACS

Keywords
PACS
  • 68.35.Ja
    Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties) Solid surfaces and solid–solid interfaces Surface and interface dynamics and vibrations
  • 68.45.Kg
    Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties) Solid–fluid interfaces Dynamics; vibrations
  • YEAR: 1999

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PUBLICATION DATA

ISSN:
0003-6951 (print)   1077-3118 (online)
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REFERENCES (28)
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