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Field-Induced Disorder Point in Non-Collinear Ising Spin Chains

A Vindigni·N Regnault·Th Jolicoeur
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Abstract

We perform a theoretical study of a non-collinear Ising ferrimagnetic spin chain inspired by the compound Co(hfac)2NITPhOMe. The basic building block of its structure contains one Cobalt ion and one organic radical each with a spin 1/2. The exchange interaction is strongly anisotropic and the corresponding axes of anisotropy have a period three helical structure. We introduce and solve a model Hamiltonian for this spin chain. We show that the present compound is very close to a so-called disorder point at which there is a massive ground state degeneracy. We predict the equilibrium magnetization process and discuss the impact of the degeneracy on the dynamical properties by using arguments based on the Glauber dynamics.

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A Vindigni, N Regnault, Th Jolicoeur. 2003-12-19. Field-Induced Disorder Point in Non-Collinear Ising Spin Chains. https://doi.org/10.1103/physrevb.70.134423

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