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arXiv · 0712.4306

An exact calculation of the transverse susceptibility for an antiferromagnetic Ising $Δ$ chain

Nobutaka Kunisada·Yoshiyuki Fukumoto
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Abstract

We study the transverse susceptibility of the fully frustrated antiferromagnetic Ising $Δ$-chain, extending Minami's transfer-matrix method for the transverse susceptibility of general-type Ising linear-chains [JPSJ 67,1998,2255]. For transverse fields $Γ_1$ on tip spin sites and $Γ_2$ on bottom spin sites, we calculate zero-field transverse-susceptibilities $χ_{tip}^x=\lim_{Γ_1,Γ_2 -> 0}M_{tip}^x/Γ_1$ and $χ_{bottom}^x=\lim_{Γ_1,Γ_2 -> 0}M^x_{bottom}/Γ_2$, where $M_{tip (bottom)}^x$ denotes the magnetization for tip (bottom) spin sites. Both the transverse susceptibilities follow Curie's law at low temperatures. We also calculate $χ_{bottom}^x(Γ_1>0)$, transverse susceptibility of the bottom spin chain under finite tip-spin transverse-fields, to understand the Curie type behavior in the zero-field susceptibility. Using the second-order perturbation theory, we discuss the $Γ_1$ dependence of $χ_{bottom}^x(Γ_1)$ at zero temperature.

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BibTeXRIS

Nobutaka Kunisada, Yoshiyuki Fukumoto. 2007-12-28. An exact calculation of the transverse susceptibility for an antiferromagnetic Ising $Δ$ chain. https://doi.org/10.1143/ptp.119.913

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