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arXiv · 1803.01492

Nested Quantum Annealing Correction at Finite Temperature: $p$-spin models

Shunji Matsuura·Hidetoshi Nishimori·Walter Vinci·Daniel A. Lidar
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Abstract

Quantum annealing in a real device is necessarily susceptible to errors due to diabatic transitions and thermal noise. Nested quantum annealing correction is a method to suppress errors by using an all-to-all penalty coupling among a set of physical qubits representing a logical qubit. We show analytically that nested quantum annealing correction can suppress errors effectively in ferromagnetic and antiferromagnetic Ising models with infinite-range interactions. Our analysis reveals that the nesting structure can significantly weaken or even remove first-order phase transitions, in which the energy gap closes exponentially. The nesting structure also suppresses thermal fluctuations by reducing the effective temperature.

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Shunji Matsuura, Hidetoshi Nishimori, Walter Vinci, Daniel A. Lidar. 2018-03-05. Nested Quantum Annealing Correction at Finite Temperature: $p$-spin models. https://doi.org/10.1103/physreva.99.062307

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