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Peculiar from-Edge-to-Interior Spin Freezing in a Magnetic Dipolar Cube

Katsuyoshi Matsushita·Ryoko Sugano·Akiyoshi Kuroda·Yusuke Tomita·Hajime Takayama
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Abstract

By molecular dynamics simulation, we have investigated classical Heisenberg spins, which are arrayed on a finite simple cubic lattice and interact with each other only by the dipole-dipole interaction, and have found its peculiar it from-Edge-to-interior freezing process. As the temperature is decreased, spins on each edge predominantly start to freeze in a ferromagnetic alignment parallel to the edge around the corresponding bulk transition temperature, then from each edges grow domains with short-range orders similar to the corresponding bulk orders, and the system ends up with a unique multi-domain ground state at the lowest temperature. We interpret this freezing characteristics is attributed to the anisotropic and long-range nature of the dipole-dipole interaction combined with a finite-size effect.

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Katsuyoshi Matsushita, Ryoko Sugano, Akiyoshi Kuroda, Yusuke Tomita, Hajime Takayama. 2005-06-02. Peculiar from-Edge-to-Interior Spin Freezing in a Magnetic Dipolar Cube. https://doi.org/10.1143/jpsj.74.2651

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