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Scattering Theory of Mesoscopic Detectors

M. Buttiker·S. Pilgram
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Abstract

We consider a two-level system coupled to a mesoscopic two-terminal conductor that acts as measuring device. As a convenient description of the conductor we introduce its scattering matrix. We show how its elements can be used to calculate the relaxation and decoherence rates of the two-level system. Special emphasis is laid on the charge screening in the conductor that becomes important in the many-channel limit. Finally we give some examples that illustrate charge screening in different limits.

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M. Buttiker, S. Pilgram. 2003-02-19. Scattering Theory of Mesoscopic Detectors. https://doi.org/10.1016/s0039-6028(03)00235-8

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