Exchange energies of kapellasite from high-temperature series analysis of the kagome lattice J 1 − J 2 − J d -Heisenberg model
Résumé
We present a method to build magnetic models for insulators based on high-temperature expansions by fitting both the magnetic susceptibility and the low temperature specific heat data. It is applied to the frustrated magnet kapellasite (Cu3Zn(OH)6Cl2) with the J1-J2-J d-Heisenberg model on the kagome lattice. Experimental data are reproduced with a set of competing exchange energies closed to J1 = −12 K, J2 = −4 K and J d = 15.6 K, where J d is the third neighbor exchange energy across the hexagon. Strong constrains between these exchange energies are established. These values confirm the results of B. Fåk et al. (Phys. Rev. Lett., 109, 037208 (2012)) regarding the location of kapellasite in the cuboc2 phase of the Heisenberg model. The quality and limits of this modeling are discussed.
Domaines
Physique [physics]Origine | Fichiers produits par l'(les) auteur(s) |
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