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arXiv · 2108.12761

Gapped ground state in a spin-1/2 frustrated square lattice

H. Yamaguchi·N. Uemoto·T. Okubo·Y. Kono·S. Kittaka·T. Sakakibara·T. Yajima·S. Shimono·Y. Iwasaki·Y. Hosokoshi
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Abstract

We present a model compound with a spin-1/2 frustrated square lattice, in which three ferromagnetic (F) interactions and one antiferromagnetic (AF) compet. Considering the effective spin-1 formed by the dominant F dimer, this square lattice can be mapped to a spin-1 spatially anisotropic triangular lattice. The magnetization curve exhibits gapped behavior indicative of a dominant one-dimensional (1D) AF correlation. In the field-induced gapless phase, the specific heat and magnetic susceptibility show a phase transition to an ordered state with 2D characteristics. These results indicate that the spin-1 Haldane state is extended to the 2D system. We demonstrate that the gapped ground state observed in the present spin-1/2 frustrated square lattice originates from the one-dimensionalization caused by frustration.

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H. Yamaguchi, N. Uemoto, T. Okubo, Y. Kono, S. Kittaka, T. Sakakibara, T. Yajima, S. Shimono, Y. Iwasaki, Y. Hosokoshi. 2021-08-29. Gapped ground state in a spin-1/2 frustrated square lattice. https://doi.org/10.1103/physrevb.104.l060411

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