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arXiv · 0902.1627

Low-temperature thermodynamics of one class of flat-band models

O Derzhko·J Richter·A Honecker
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Abstract

We consider the antiferromagnetic Heisenberg model and the repulsive Hubbard model for a class of frustrated lattices with a completely dispersionless (flat) lowest one-particle (either one-magnon or one-electron) band. We construct exact many-particle ground states for a wide range of particle densities, calculate their degeneracy, and, as a result, obtain closed-form expressions for the low-temperature thermodynamic quantities around a particular value of the magnetic field $h_{\rm{sat}}$ or the chemical potential $μ_0$. We confirm our analytic findings by numerical data for finite lattices.

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O Derzhko, J Richter, A Honecker. 2009-02-10. Low-temperature thermodynamics of one class of flat-band models. https://doi.org/10.1088/1742-6596/145/1/012059

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