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Conductance of Disordered Wires with Symplectic Symmetry: Comparison between Odd- and Even-Channel Cases

Yositake Takane
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Abstract

The conductance of disordered wires with symplectic symmetry is studied by numerical simulations on the basis of a tight-binding model on a square lattice consisting of M lattice sites in the transverse direction. If the potential range of scatterers is much larger than the lattice constant, the number N of conducting channels becomes odd (even) when M is odd (even). The average dimensionless conductance g is calculated as a function of system length L. It is shown that when N is odd, the conductance behaves as g --> 1 with increasing L. This indicates the absence of Anderson localization. In the even-channel case, the ordinary localization behavior arises and g decays exponentially with increasing L. It is also shown that the decay of g is much faster in the odd-channel case than in the even-channel case. These numerical results are in qualitative agreement with existing analytic theories.

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Yositake Takane. 2004-11-18. Conductance of Disordered Wires with Symplectic Symmetry: Comparison between Odd- and Even-Channel Cases. https://doi.org/10.1143/jpsj.73.2366

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