Abstract
Within the framework of the scattering matrix formalism, the nonlinear Kubo theory for electron transport in the metal with a tunnel barrier has been considered. A general expression for the mean electrical current was obtained. It significantly simplifies the calculation of nonlinear contributions to the conductivity of various hybrid structures. In the model of the tunnel Hamiltonian, all linear and nonlinear contributions to a mean electrical current are evaluated. The linear approximation agrees with results of other theories. For effective barrier transmission , the ballistic transport is realised with a value of the Landauer conductivity equal to
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Acknowledgements
It is a pleasure to acknowledge a number of stimulating discussions with E. M. Rudenko, M. A. Belogolovskii and A. P. Shapovalov.
Notes
No potential conflict of interest was reported by the authors.