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arXiv · 0803.1710

Spin-lattice model of Magneto-electric Transitions in RbCoBr$_3$

Tota Nakamura·Yoichi Nishiwaki
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Abstract

Extensive Monte Carlo simulations are performed to analyze a recent neutron diffraction experiment on a distorted triangular lattice compound RbCoBr$_3$. We consider a spin-lattice model, where both spin and lattice are Ising variables. This model explains well successive magnetic and dielectric transitions observed in the experiment. The exchange interaction parameters and the spin-lattice coupling are estimated. It is found that the spin-lattice coupling is important to explain the slow growth of a ferrimagnetic order. The present simulations were made possible by developing a new Monte Carlo algorithm, which accelerates slow Monte Carlo dynamics of quasi-one-dimensional frustrated systems.

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Tota Nakamura, Yoichi Nishiwaki. 2008-09-02. Spin-lattice model of Magneto-electric Transitions in RbCoBr$_3$. https://doi.org/10.1103/physrevb.78.104422

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