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arXiv · 2012.01694

Variational optimization of the quantum annealing schedule for the Lechner-Hauke-Zoller scheme

Yuki Susa·Hidetoshi Nishimori
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Abstract

The annealing schedule is optimized for a parameter in the Lechner-Hauke-Zoller (LHZ) scheme for quantum annealing designed for the all-to-all-interacting Ising model representing generic combinatorial optimization problems. We adapt the variational approach proposed by Matsuura et al. (arXiv:2003.09913) to the annealing schedule of a term representing a constraint for variables intrinsic to the LHZ scheme with the annealing schedule of other terms kept intact. Numerical results for a simple ferromagnetic model and the spin-glass problem show that nonmonotonic annealing schedules optimize the performance measured by the residual energy and the final ground-state fidelity. This improvement does not accompany a notable increase in the instantaneous energy gap, which suggests the importance of a dynamical viewpoint in addition to static analyses in the study of practically relevant diabatic processes in quantum annealing.

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Yuki Susa, Hidetoshi Nishimori. 2021-03-01. Variational optimization of the quantum annealing schedule for the Lechner-Hauke-Zoller scheme. https://doi.org/10.1103/physreva.103.022619

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