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S-matrix network models for coherent waves in random media: construction and renormalization

Martin Janssen·Rainer Merkt·Andreas Weymer
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Abstract

Networks of random quantum scatterers (S-matrices) form paradigmatic models for the propagation of coherent waves in random S-matrix network models cover universal localization-delocalization properties and have some advantages over more traditional Hamiltonian models. In particular, a straightforward implementation of real space renormalization techniques is possible. Starting from a finite elementary cell of the S-matrix network, hierarchical network models can be constructed by recursion. The localization-delocalization properties are contained in the flow of the forward scattering strength ('conductance') under increasing system size. With the aid of 'small scale' numerics qualitative aspects of the localization-delocalization properties of S-matrix network models can be worked out.

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Martin Janssen, Rainer Merkt, Andreas Weymer. 1998-10-13. S-matrix network models for coherent waves in random media: construction and renormalization. https://doi.org/10.1002/(sici)1521-3889(199811)7%3A5%2F6%3C353%3A%3Aaid-andp353%3E3.0.co%3B2-9

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