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arXiv · 1406.4964

Spin-Flop Phenomenon of Two-Dimensional Frustrated Antiferromagnets without Anisotropy in Spin Space

Hiroki Nakano·Toru Sakai·Yasumasa Hasegawa
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Abstract

Motivated by a recent finding of a spin-flop phenomenon in a system without anisotropy in spin space reported in the S=1/2 Heisenberg antiferromagnet on the square-kagome lattice, we study the S=1/2 Heisenberg antiferromagnets on two other lattices composed of vertex-sharing triangles by the numerical diagonalization method. One is a novel lattice including a shuriken shape with four teeth; the other is the kagome lattice with $\sqrt{3}\times\sqrt{3}$-structure distortion, which includes a shuriken shape with six teeth. We find in the magnetization processes of these systems that a magnetization jump accompanied by a spin-flop phenomenon occurs at the higher-field-side edge of the magnetization plateau at one-third the height of saturation. This finding indicates that the spin-flop phenomenon found in the isotropic system on the square-kagome lattice is not an exceptional case.

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Hiroki Nakano, Toru Sakai, Yasumasa Hasegawa. 2014-06-19. Spin-Flop Phenomenon of Two-Dimensional Frustrated Antiferromagnets without Anisotropy in Spin Space. https://doi.org/10.7566/jpsj.83.084709

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