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arXiv · 1708.03764

Ground state study of a double core-shell dendrimer nanostructure

Abstract

Based on a dendrimer graph theory, we investigate the ground state phase diagrams of a nanostructure formed by three spins: $\sigma=1/2$, S=1 and q=3/2. This nanostructure is built on a dendrimer with triangular core geometry. More precisely, we evaluate the effect of different physical parameters including the exchange interactions, the external magnetic and the crystal fields. By varying these parameters, we analytically elaborate the ground state phase diagrams. Concretely, we found that the existence of the crystal field increases the number of stable phases. The total number of possible phases is 24=2x3x4, which are: ($\pm$1/2,$\pm$1,$\pm$3/2), ($\pm$1/2,0,$\pm$3/2), ($\pm$1/2,$\pm$1,$\pm$1/2) and ($\pm$1/2,0,$\pm$1/2). All these phases are found to be stable, expect two special phases: (+1/2,0,-3/2) and (-1/2,0,+3/2), which are masked by the other phases in all the ground state phase diagrams.

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H. Labrim, A. Belhaj, S. Ziti, L. Bahmad, A. Elmorabiti, L. Laanab, S. Benmokhtar, A. Benyoussef. 2017-08-12. Ground state study of a double core-shell dendrimer nanostructure. https://arxiv.org/abs/1708.03764

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