Gauge-Invariant Formulation of Fermi's Golden Rule: Application to High-Field Transport in Semiconductors

Emanuele Ciancio; Fausto Rossi

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Gauge-Invariant Formulation of Fermi's Golden Rule: Application to High-Field Transport in Semiconductors

Emanuele Ciancio·Fausto Rossi

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Abstract

A gauge-invariant formulation of Fermi's Golden rule is proposed. We shall rivisit the conventional description of carrier-phonon scattering in the presence of high electric fields by means of a gauge-invariant density-matrix approach. We show that the so-called Intracollisional Field Effect - as usually accounted for - does not exist: it is simply an artifact due to the neglect of the time variation of the basis states which, in turn, leads to a ill-defined Markov limit in the carrier-phonon interaction process. This may account for the surprisingly good agreement between semiclassical and rigorous quantum-transport calculations.

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Emanuele Ciancio, Fausto Rossi. 2001-05-25. Gauge-Invariant Formulation of Fermi's Golden Rule: Application to High-Field Transport in Semiconductors. https://arxiv.org/abs/cond-mat/0105495

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