Time-dependent theory of non-linear response and current fluctuations

Ines Safi

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arXiv · 0908.4382

Time-dependent theory of non-linear response and current fluctuations

Ines Safi

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Abstract

A general non-linear response theory is derived for an arbitrary time-dependent Hamiltonian, not necessarily obeying time-reversal symmetry. This allows us to obtain a greatly generalized Kubo type formula. Applied to a mesoscopic system with any type of interactions, and coupled to multiple probes and gates with arbitrarily time-dependent voltages, we derive current-conserving differential conductance and current fluctuation matrices obeying a generalized Fluctuation-Dissipation Theorem. This relation provides a common explanation for asymmetries of the excess noise in several non-linear mesoscopic systems, as well as of its surprising negative sign.

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Ines Safi. 2009-10-30. Time-dependent theory of non-linear response and current fluctuations. https://arxiv.org/abs/0908.4382

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