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Two-level system with a thermally fluctuating transfer matrix element: Application to the problem of DNA charge transfer

Maria R. D'Orsogna·Joseph Rudnick
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Abstract

Charge transfer along the base-pair stack in DNA is modeled in terms of thermally-assisted tunneling between adjacent base pairs. Central to our approach is the notion that tunneling between fluctuating pairs is rate-limited by the requirement of their optimal alignment. We focus on this aspect of the process by modeling two adjacent base pairs in terms of a classical damped oscillator subject to thermal fluctuations as described by a Fokker-Planck equation. We find that the process is characterized by two time scales, a result that is in accord with experimental findings.

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Maria R. D'Orsogna, Joseph Rudnick. 2002-07-26. Two-level system with a thermally fluctuating transfer matrix element: Application to the problem of DNA charge transfer. https://doi.org/10.1103/physreve.66.041804

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