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arXiv · 1508.07072

Rigorous determination of the ground-state phases and thermodynamics in an Ising-type multiferroic Ca3CoMnO6 chain

Yan Qi·Qi Yang·Nai-sen Yu·An Du
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Abstract

To understand the collinear-magnetism-driven ferroelectricity in multiferroic Ca3CoMnO6 compound, we have established an elastic diatomic Ising spin-chain model with axial-next-nearest-neighbor interaction to describe its magnetoelectric properties. By employing magneto-phonon decoupling and transfer-matrix method, the possible ground-state configurations and thermodynamic behaviors of the system have been exactly determined. From the perspective of the ground-state configuration, we analyze the computational results and make a detail comparison with experimental data. The parameter relation for the appearance of electric polarization has been discussed. Our data indicate that the magnetic coupling between nearest-neighbor spin pair is antiferromagnetic rather than ferromagnetic. The system under the driven of external magnetic field undergoes a different series of transitions from the up-up-down-down spin configuration to the up-down-up state with peculiar 1/3 magnetization plateau, then to the up-up-up-down state, and finally saturated at up-up-up-up state.

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Yan Qi, Qi Yang, Nai-sen Yu, An Du. 2015-08-28. Rigorous determination of the ground-state phases and thermodynamics in an Ising-type multiferroic Ca3CoMnO6 chain. https://doi.org/10.1088/0953-8984%2F28%2F12%2F126006

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