Vibrational Instability due to Coherent Tunneling of Electrons

EPL (Europhysics Letters) (Impact Factor: 2.26). 04/2001; DOI: 10.1209/epl/i2002-00611-3
Source: arXiv

ABSTRACT Effects of a coupling between the mechanical vibrations of a quantum dot placed between the two leads of a single electron transistor and coherent tunneling of electrons through a single level in the dot has been studied. We have found that for bias voltages exceeding a certain critical value a dynamical instability occurs and mechanical vibrations of the dot develop into a stable limit cycle. The current-voltage characteristics for such a transistor were calculated and they seem to be in a reasonably good agreement with recent experimental results for the single $C_{60}$-molecule transistor by Park et al.(Nature {\bf 407,} (2000) 57). Comment: 5 pages, 3 figures

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