The superspin approach to a disordered quantum wire in the chiral-unitary symmetry class with an arbitrary number of channels - Condensed Matter > Disordered Systems and Neural NetworksReport as inadecuate




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Abstract: We use a superspin Hamiltonian defined on an infinite-dimensional Fock spacewith positive definite scalar product to study localization and delocalizationof noninteracting spinless quasiparticles in quasi-one-dimensional quantumwires perturbed by weak quenched disorder. Past works using this approach haveconsidered a single chain. Here, we extend the formalism to treat aquasi-one-dimensional system: a quantum wire with an arbitrary number ofchannels coupled by random hopping amplitudes. The computations are carried outexplicitly for the case of a chiral quasi-one-dimensional wire with brokentime-reversal symmetry chiral-unitary symmetry class. By treating the spacedirection along the chains as imaginary time, the effects of the disorder areencoded in the time evolution induced by a single site superspinnon-Hermitian Hamiltonian. We obtain the density of states near the bandcenter of an infinitely long quantum wire. Our results agree with those basedon the Dorokhov-Mello-Pereyra-Kumar equation for the chiral-unitary symmetryclass.



Author: Andreas P. Schnyder, Christopher Mudry, Ilya A. Gruzberg

Source: https://arxiv.org/







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