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Quasi-periodic spin chains in a magnetic field

M. Arlego·D. C. Cabra·M. D. Grynberg
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Abstract

We study the interplay between a (quasi) periodic coupling array and an external magnetic field in a spin-1/2 XXZ chain. A new class of magnetization plateaux are obtained by means of Abelian bosonization methods which give rise to a sufficient quantization condition. The investigation of magnetic phase diagrams via exact diagonalization of finite clusters finds a complete agreement with the continuum treatment in a variety of situations.

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M. Arlego, D. C. Cabra, M. D. Grynberg. 2001-10-15. Quasi-periodic spin chains in a magnetic field. https://doi.org/10.1103/physrevb.64.134419

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