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Interplay between quasi-periodicity and disorder in quantum spin chains in a magnetic field

Marcelo Arlego
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Abstract

We study the interplay between disorder and a quasi periodic coupling array in an external magnetic field in a spin-1/2 XXZ chain. A simple real space decimation argument is used to estimate the magnetization values where plateaux show up. The latter are in good agreement with exact diagonalization results on fairly long XX chains. Spontaneous susceptibility properties are also studied, finding a logarithmic behaviour similar to the homogeneously disordered case.

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Marcelo Arlego. 2002-01-24. Interplay between quasi-periodicity and disorder in quantum spin chains in a magnetic field. https://doi.org/10.1103/physrevb.66.052419

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