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Probing Pauli Blocking Factors in Quantum Pumps with Broken Time-Reversal Symmetry

Mathias Wagner
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Abstract

A recently demonstrated quantum electron pump is discussed within the framework of photon-assisted tunneling. Due to lack of time-reversal symmetry, different results are obtained for the pump current depending on whether or not final-state Pauli blocking factors are used when describing the tunneling process. Whilst in both cases the current depends quadratically on the driving amplitude for moderate pumping, a marked difference is predicted for the temperature dependence. With blocking factors the pump current decreases roughly linearly with temperature until k_B T ~ \hbarωis reached, whereas without them it is unaffected by temperature, indicating that the entire Fermi sea participates in the electronic transport.

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Mathias Wagner. 2000-06-21. Probing Pauli Blocking Factors in Quantum Pumps with Broken Time-Reversal Symmetry. https://doi.org/10.1103/physrevlett.85.174

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