Spin-detection in a quantum electromechanical shuttle system

J. Twamley*, D. W. Utami, H. S. Goan, G. Milburn

*Corresponding author for this work

    Research output: Contribution to journalArticlepeer-review

    22 Citations (Scopus)
    15 Downloads (Pure)


    We study the electrical transport of a harmonically bound, single-molecule C60 shuttle operating in the Coulomb blockade regime, i.e. single electron shuttling. In particular, we examine the dependance of the tunnel current on an ultra-small stationary force exerted on the shuttle. As an example, we consider the force exerted on an endohedral N@C60 by the magnetic field gradient generated by a nearby nanomagnet. We derive a Hamiltonian for the full shuttle system which includes the metallic contacts, the spatially dependent tunnel couplings to the shuttle, the electronic and motional degrees of freedom of the shuttle itself and a coupling of the shuttle's motion to a phonon bath. We analyse the resulting quantum master equation and find that, due to the exponential dependence of the tunnel probability on the shuttle-contact separation, the current is highly sensitive to very small forces. In particular, we predict that the spin state of the endohedral electrons of NOC60 in a large magnetic gradient field can be distinguished from the resulting current signals within a few tens of nanoseconds. This effect could prove useful for the detection of the endohedral spin-state of individual paramagnetic molecules such as N@C60 and P@C60, or the detection of very small static forces acting on a C60 shuttle.

    Original languageEnglish
    Article number63
    Pages (from-to)2-27
    Number of pages26
    JournalNew Journal of Physics
    Publication statusPublished - 2 May 2006

    Bibliographical note

    Copyright 2006 IOP Publishing Ltd. Reprinted from New journal of physics. This material is posted here with the permission of IOP Publishing Ltd and the authors. Use of this material is permitted for personal, research and non-commercial uses. Further information regarding the copyright applicable to this article can be viewed at http://www.iop.org/EJ/journal/-page=extra.copyright/NJP.


    Dive into the research topics of 'Spin-detection in a quantum electromechanical shuttle system'. Together they form a unique fingerprint.

    Cite this