title: Closed-loop conductance scanning tunneling spectroscopy: demonstrating the equivalence to the open-loop alternative.
abstract: We demonstrate the validity of using closed-loop z(V) conductance scanning tunneling spectroscopy (STS) measurements for the determination of the effective tunneling barrier by comparing them to more conventional open-loop I(z) measurements. Through the development of a numerical model, the individual contributions to the effective tunneling barrier present in these experiments, such as the work function and the presence of an image charge, are determined quantitatively. This opens up the possibility of determining tunneling barriers of both vacuum and molecular systems in an alternative and more detailed manner.
authors.affiliation: Physics of Interfaces and Nanomaterials, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE, Enschede, Netherlands.
authors.forename: Chris
authors.initials: C
authors.lastname: Hellenthal
authors.affiliation: Physics of Interfaces and Nanomaterials, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE, Enschede, Netherlands.
authors.forename: Kai
authors.initials: K
authors.lastname: Sotthewes
authors.affiliation: Physics of Interfaces and Nanomaterials, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE, Enschede, Netherlands.
authors.forename: Martin H
authors.initials: MH
authors.lastname: Siekman
authors.affiliation: Physics of Interfaces and Nanomaterials, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE, Enschede, Netherlands.
authors.forename: E Stefan
authors.initials: ES
authors.lastname: Kooij
authors.affiliation: Physics of Interfaces and Nanomaterials, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE, Enschede, Netherlands.
authors.forename: Harold J W
authors.initials: HJ
authors.lastname: Zandvliet
keywords: image charge; scanning tunneling spectroscopy (STS); tunneling barrier; work function; z(V)