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Spin-3/2 random quantum antiferromagnetic chains

A. Saguia·B. Boechat·M. A. Continentino
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Abstract

We use a modified perturbative renormalization group approach to study the random quantum antiferromagnetic spin-3/2 chain. We find that in the case of rectangular distributions there is a quantum Griffiths phase and we obtain the dynamical critical exponent $Z$ as a function of disorder. Only in the case of extreme disorder, characterized by a power law distribution of exchange couplings, we find evidence that a random singlet phase could be reached. We discuss the differences between our results and those obtained by other approaches.

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A. Saguia, B. Boechat, M. A. Continentino. 2003-08-04. Spin-3/2 random quantum antiferromagnetic chains. https://doi.org/10.1103/physrevb.68.020403

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