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arXiv · cond-mat/0310703

Landauer conductance of tunnel junctions: Strong impact from boundary conditions

Abstract

We present model calculations for the Landauer conductance of tunnel junctions. The tunneling of free electrons through a rectangular potential barrier is considered. The conductance of a finite number of barriers was calculated using a transfer matrix method. The periodic arrangement of the same barriers was described by a Kronig-Penney model to calculate the band structure and from that the conductance of a point contact in the ballistic limit. The comparison of both results elucidated the importance of the boundary conditions. Caused by resonant scattering in the superlattice the conductance is overestimated by the order of 1/t, the transmission coefficient of the single barrier. In the case of metallic multilayers these interferences are of minor importance. In conclusion, the application of the Landauer formula to periodic lattices to describe the tunneling conductance of a single barrier is not correct.

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Peter Zahn, Ingrid Mertig. 2003-10-29. Landauer conductance of tunnel junctions: Strong impact from boundary conditions. https://doi.org/10.1080/14786430410001716188

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