Magnetization Process of the Spin-1/2 Triangular-Lattice Heisenberg Antiferromagnet with Next-Nearest-Neighbor Interactions -- Plateau or Nonplateau

Hiroki Nakano; Toru Sakai

doi:10.7566/jpsj.86.114705

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arXiv · 1708.07248

Magnetization Process of the Spin-1/2 Triangular-Lattice Heisenberg Antiferromagnet with Next-Nearest-Neighbor Interactions -- Plateau or Nonplateau

Hiroki Nakano·Toru Sakai

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Abstract

An $S=1/2$ triangular-lattice Heisenberg antiferromagnet with next-nearest-neighbor interactions is investigated under a magnetic field by the numerical-diagonalization method. It is known that, in both cases of weak and strong next-nearest-neighbor interactions, this system reveals a magnetization plateau at one-third of the saturated magnetization. We examine the stability of this magnetization plateau when the amplitude of next-nearest-neighbor interactions is varied. We find that a nonplateau region appears between the plateau phases in the cases of weak and strong next-nearest-neighbor interactions.

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Hiroki Nakano, Toru Sakai. 2017-08-24. Magnetization Process of the Spin-1/2 Triangular-Lattice Heisenberg Antiferromagnet with Next-Nearest-Neighbor Interactions -- Plateau or Nonplateau. https://doi.org/10.7566/jpsj.86.114705

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