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arXiv · 2206.05590

Quantum Heisenberg model on a sawtooth-chain lattice: Rotation-invariant Green's function method

Taras Hutak·Taras Krokhmalskii·Oleg Derzhko·Johannes Richter
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Abstract

We apply the rotation-invariant Green's function method (RGM) to study the spin $S=1/2$ Heisenberg model on a one-dimensional sawtooth lattice, which has two nonequivalent sites in the unit cell. We check the RGM predictions for observable quantities by comparison with the exact-diagonalization and finite-temperature-Lanczos calculations. We discuss the thermodynamic and dynamic properties of this model in relation to the mineral atacamite Cu$_2$Cl(OH)$_3$ complementing the RGM outcomes by results of other approaches.

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Taras Hutak, Taras Krokhmalskii, Oleg Derzhko, Johannes Richter. 2022-06-11. Quantum Heisenberg model on a sawtooth-chain lattice: Rotation-invariant Green's function method. https://doi.org/10.1140/epjb%2Fs10051-022-00359-0

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