Magnetic properties of two-dimensional dipolar squares: Boundary geometry dependence

Ryoko Sugano, Katsuyoshi Matsushita, Akiyoshi Kuroda, Yusuke Tomita, Hajime Takayama

研究成果: Article

2 引用 (Scopus)

抄録

By means of the molecular dynamics simulation of gradual cooling processes, we investigate magnetic properties of classical spin systems only with the magnetic dipole-dipole interaction, which we call dipolar systems. Focusing on their finite-size effect, particularly their boundary geometry dependence, we study two finite dipolar squares cut out from a square lattice with Φ = 0 and π/4, where Φ is the angle between the direction of the lattice axis and that of the square boundary. Distinctly different results are obtained in the two dipolar squares. In the Φ = 0 square, the "from-edge-to- interior freezing" of spins is observed. Its ground state has a multidomain structure whose domains consist of two among infinitely (continuously) degenerated Luttinger-Tisza (LT) ground-state orders on a bulk square lattice, i.e., the two antiferromagnetically aligned ferromagnetic chains (af-FMC) orders directed parallel to the two lattice axes. In the Φ = π/4 square, on the other hand, the freezing starts from the interior of the square, and its ground state is nearly in a single domain with one of the two af-FMC orders. These geometry effects are argued to originate from the anisotropic nature of the dipole-dipole interaction, which depends on the relative direction of sites in the real space of the interacting spins.

元の言語English
記事番号044705
ジャーナルJournal of the Physical Society of Japan
76
発行部数4
DOI
出版物ステータスPublished - 2007 4
外部発表Yes

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magnetic properties
dipoles
geometry
freezing
ground state
magnetic dipoles
interactions
molecular dynamics
cooling
simulation

ASJC Scopus subject areas

  • Physics and Astronomy(all)

これを引用

Magnetic properties of two-dimensional dipolar squares : Boundary geometry dependence. / Sugano, Ryoko; Matsushita, Katsuyoshi; Kuroda, Akiyoshi; Tomita, Yusuke; Takayama, Hajime.

:: Journal of the Physical Society of Japan, 巻 76, 番号 4, 044705, 04.2007.

研究成果: Article

Sugano, Ryoko ; Matsushita, Katsuyoshi ; Kuroda, Akiyoshi ; Tomita, Yusuke ; Takayama, Hajime. / Magnetic properties of two-dimensional dipolar squares : Boundary geometry dependence. :: Journal of the Physical Society of Japan. 2007 ; 巻 76, 番号 4.
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