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

TL;DR

This paper demonstrates that inhomogeneous driving of the transverse field in quantum annealing can eliminate first-order phase transitions, leading to exponential speedups in the annealing process for certain models.

Contribution

It introduces a simple inhomogeneous driving protocol that removes first-order transitions, enhancing quantum annealing efficiency beyond existing methods.

Findings

Eliminates first-order quantum phase transitions in mean-field models.

Achieves exponential speedup in quantum annealing due to transition removal.

Provides a practical protocol for improving quantum annealing performance.

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.