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arXiv · 2409.16715

Collapsing Behavior of the Ferrimagnetic Ground State of the $S=1/2$ Heisenberg Antiferromagnet on the Lieb Lattice due to Frustration

Rito Furuchi·Hiroki Nakano·Tôru Sakai
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Abstract

We study the $S = 1/2$ Heisenberg antiferromagnet on the Lieb lattice accompanied by additional interactions that create frustration. The system exhibits a ferrimagnetic ground state in the absence of frustration. Further, we successfully observe a novel type of collapsing behavior of the ferrimagnetism via numerical diagonalization. The ferrimagnetic state is observed to collapse in a discontinuous manner. Furthermore, different ground states with small spontaneous magnetizations are obtained before the spontaneous magnetization finally disappears.

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Rito Furuchi, Hiroki Nakano, Tôru Sakai. 2024-09-25. Collapsing Behavior of the Ferrimagnetic Ground State of the $S=1/2$ Heisenberg Antiferromagnet on the Lieb Lattice due to Frustration. https://doi.org/10.7566/jpsj.93.115002

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