equilibrium noise suppression by modulating contact transparency
DESCRIPTION
Equilibrium Noise Suppression by Modulating Contact Transparency Y. B. Sherkunov, Jin Zhang, N. d'Ambrumenil, B. Muzykantskii Department of Physics, University of Warwick, Coventry, CV4 7AL, U.K . A. when. 0. t. ABSTRACT - PowerPoint PPT PresentationTRANSCRIPT
Equilibrium Noise Suppression by Modulating Contact TransparencyY. B. Sherkunov, Jin Zhang, N. d'Ambrumenil, B. Muzykantskii
Department of Physics, University of Warwick, Coventry, CV4 7AL, U.K.
ABSTRACTControlled injection of single electrons into a ballistic conductor is essential for ``moving-electron-based'' quantum computation. We obtain the full counting statistics (FCS) of a quantum point contact (QPC) for the case when the contact transparency is modulated in time, which is shown to be equivalent to a system with a time-dependent bias voltage applied between the leads. We demonstrate two optimal contact opening schemes with the equilibrium noise largely suppressed. The potential applications includes an optimal electronic entangler and on-demand single electron source.
Scattering Matrix Approach
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Mapping Method for Modulating Contact Transparency
Noise Minimization for QPC?
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References:Ivanov, Lee, Levitov, Phys. Rev. B 56, 6839 (1997)Keeling, Klich, Levitov, Phys. Rev. Lett. 97, 116403 (2006)Abanov and Ivanov, Phys. Rev. Lett. 100, 086602 (2008)YS, JZ, NdA, BM, arXiv:0812.4433v3JZ, YS, NdA, BM, in preparation
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