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arXiv · 1801.02005

Exponential Speedup of Quantum Annealing by Inhomogeneous Driving of the Transverse Field

Yuki Susa·Yu Yamashiro·Masayuki Yamamoto·Hidetoshi Nishimori
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Abstract

We show, for quantum annealing, that a certain type of inhomogeneous driving of the transverse field erases first-order quantum phase transitions in the p-body interacting mean-field-type model with and without longitudinal random field. Since a first-order phase transition poses a serious difficulty for quantum annealing (adiabatic quantum computing) due to the exponentially small energy gap, the removal of first-order transitions means an exponential speedup of the annealing process. The present method may serve as a simple protocol for the performance enhancement of quantum annealing, complementary to non-stoquastic Hamiltonians.

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Yuki Susa, Yu Yamashiro, Masayuki Yamamoto, Hidetoshi Nishimori. 2018-01-06. Exponential Speedup of Quantum Annealing by Inhomogeneous Driving of the Transverse Field. https://doi.org/10.7566/jpsj.87.023002

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