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arXiv · 1510.06185

Effective low-energy description of almost Ising-Heisenberg diamond chain

Oleg Derzhko·Olesia Krupnitska·Bohdan Lisnyi·Jozef Strecka
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Abstract

We consider a geometrically frustrated spin-1/2 Ising-Heisenberg diamond chain, which is an exactly solvable model when assuming part of the exchange interactions as Heisenberg ones and another part as Ising ones. A small $XY$ part is afterwards perturbatively added to the Ising couplings, which enabled us to derive an effective Hamiltonian describing the low-energy behavior of the modified but full quantum version of the initial model. The effective model is much simpler and free of frustration. It is shown that the $XY$ part added to the originally Ising interaction gives rise to the spin-liquid phase with continuously varying magnetization, which emerges in between the magnetization plateaus and is totally absent in the initial hybrid diamond-chain model. The elaborated approach can also be applied to other hybrid Ising-Heisenberg spin systems.

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Oleg Derzhko, Olesia Krupnitska, Bohdan Lisnyi, Jozef Strecka. 2015-10-21. Effective low-energy description of almost Ising-Heisenberg diamond chain. https://doi.org/10.1209/0295-5075%2F112%2F37002

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