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arXiv · 2209.13105

Large-Scale Numerical-Diagonalization Study of the Shastry-Sutherland Model

Hiroki Nakano·Toru Sakai
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Abstract

The $S=1/2$ Heisenberg antiferromagnet on the orthogonal-dimer lattice (Shastry-Sutherland model) is studied by the Lanczos diagonalization method. The properties of this model are determined by the ratio of two interactions, namely, $r=J_2/J_1$, where $J_1$ denotes the amplitude of spin interactions at orthogonal dimers and the interactions represented by $J_2$ form the square lattice. We focus our attention on the edge of the phase in which the dimer state is realized as the exact ground state. Our large-scale calculations of diagonalizations treating finite-size clusters including 44 and 48 spin sites successfully detect the target edge. Our conclusion is that the ratio for the edge is $r= 0.6754(2)$. This estimate is compared with an experimental result from electron spin resonance measurements.

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Hiroki Nakano, Toru Sakai. 2022-09-27. Large-Scale Numerical-Diagonalization Study of the Shastry-Sutherland Model. https://doi.org/10.7566/jpscp.38.011166

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