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Phase diagram of a coupled tetrahedral Heisenberg model

Onofre Rojas·F. C. Alcaraz
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Abstract

The phase diagram of a coupled tetrahedral Heisenberg model is obtained. The quantum chain has a local gauge symmetry and its eigenspectrum is obtained by the composition of the eigenspectra of spin-1/2 XXZ chains with arbitrary distribution of spin-3/2 impurities. The phase diagram is quite rich with an infinite number of phases with ferromagnetic, antiferromagnetic or ferrimagnetic order. In some cases the ground state and the low lying eigenlevels of the model can be exactly calculated since they coincide with the eigenlevels of the exactly integrable XXZ chain. The thermodynamical properties of the model at low temperatures is also studied through finite-size analysis.

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BibTeXRIS

Onofre Rojas, F. C. Alcaraz. 2003-03-02. Phase diagram of a coupled tetrahedral Heisenberg model. https://doi.org/10.1103/physrevb.67.174401

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