After an introduction and an overview of quantum annealing, I describe recent developments in non-traditional protocols to control quantum effects for enhanced performance: (i) non-stoquastic drivers [1], (ii) spatially inhomogeneous driving of the field [2], and (iii) reverse annealing [3]. I will show explicit examples in which first-order quantum phase transitions can be avoided by these methods, implying an exponential speedup in comparison with the traditional simple transverse-field driving.
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[2] Y. Susa, Y. Yamashiro, M. Yamamoto and H. Nishimori, J. Phys. Soc. Jpn. 87, 023022 (2018), Susa, Y. Yamashiro, M. Yamamoto, I. Hen, D.A. Lidar and H. Nishimori, Phys. Rev. A 98, 042326 (2018)
[3] M. Ohkuwa, H. Nishimori, and D.A. Lidar, Phys. Rev. A 98, 022314 (2018).