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arXiv · 2202.05927

Energy landscape transformation of Ising problem with invariant eigenvalues for quantum annealing

Toru Fujii·Koshi Komuro·Yosuke Okudaira·Ryo Narita·Masayasu Sawada
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Abstract

Quantum annealing tends to be more difficult as the energy landscape of the problem becomes complicated with many local minima. We have found a transformation for changing the energy landscape that swaps the eigenvalues and paired states without changing the eigenvalues of the instance at all. The transformation is basically a partial recombination of the two-spin interaction coefficient Jij and the longitudinal magnetic field interaction coefficient hi. The Hamming distance corresponding to a barrier between the states changes by the transformation, which in turn affects the ground state convergence. In the quantum annealing simulation results of a small number of spin instances, the annealing time was shortened by several orders of magnitude by applying the transformation. In addition, we also obtained a result using a D-Wave quantum annealer, which also showed a big improvement in the ground state convergence.

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Toru Fujii, Koshi Komuro, Yosuke Okudaira, Ryo Narita, Masayasu Sawada. 2022-02-11. Energy landscape transformation of Ising problem with invariant eigenvalues for quantum annealing. https://arxiv.org/abs/2202.05927

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