title: Radio-frequency capacitance spectroscopy of metallic nanoparticles.
abstract: Recent years have seen great progress in our understanding of the electronic properties of nanomaterials in which at least one dimension measures less than 100 nm. However, contacting true nanometer scale materials such as individual molecules or nanoparticles remains a challenge as even state-of-the-art nanofabrication techniques such as electron-beam lithography have a resolution of a few nm at best. Here we present a fabrication and measurement technique that allows high sensitivity and high bandwidth readout of discrete quantum states of metallic nanoparticles which does not require nm resolution or precision. This is achieved by coupling the nanoparticles to resonant electrical circuits and measurement of the phase of a reflected radio-frequency signal. This requires only a single tunnel contact to the nanoparticles thus simplifying device fabrication and improving yield and reliability. The technique is demonstrated by measurements on 2.7 nm thiol coated gold nanoparticles which are shown to be in excellent quantitative agreement with theory.
authors.affiliation: Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom.
authors.forename: James C
authors.initials: JC
authors.lastname: Frake
authors.affiliation: Materials and Structures Laboratory, Tokyo Institute of Technology, Yokohama 226-8503, Japan.
authors.forename: Shinya
authors.initials: S
authors.lastname: Kano
authors.affiliation: Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom.
authors.forename: Chiara
authors.initials: C
authors.lastname: Ciccarelli
authors.affiliation: Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Griffiths
authors.affiliation: 1] Institute for Chemical Research, Kyoto University, Uji 611-0011, Japan [2] PRESTO, Japan Science and Technology Agency, Uji 611-0011, Japan.
authors.forename: Masanori
authors.initials: M
authors.lastname: Sakamoto
authors.affiliation: Institute for Chemical Research, Kyoto University, Uji 611-0011, Japan.
authors.forename: Toshiharu
authors.initials: T
authors.lastname: Teranishi
authors.affiliation: Materials and Structures Laboratory, Tokyo Institute of Technology, Yokohama 226-8503, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Majima
authors.affiliation: Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom.
authors.forename: Charles G
authors.initials: CG
authors.lastname: Smith
authors.affiliation: 1] London Centre for Nanotechnology, UCL, London WC1H 0AH, United Kingdom [2] Department of Physics and Astronomy, UCL, London WC1E 6BT, United Kingdom.
authors.forename: Mark R
authors.initials: MR
authors.lastname: Buitelaar