Скачать или смотреть INQA Conference 2023: Matthias Werner, Qilimanjaro Quantum Tech, Spain

Title: A strategy exploiting coherence for diabatic quantum annealing

Abstract: In recent years there have been great advances in improving the coherence of quantum annealing hardware. First experiments show the presence of coherence in large devices, sparking hopes for quantum advantage through quantum annealers. However, it is an open question how quantum annealers can exploit coherence to successfully solve computational problems. Here, we propose an explanation for the
utility of a particular coherent effect. We discuss how the interference between amplitudes of different energy levels after consecutive Landau-Zener crossings, also known as Landau-Zener-Stückelberg (LZS) interference, can be used to solve and, in some cases, speed-up the preparation of the ground state of a target Hamiltonian. Based on our previous work on first-order quantum phase transitions (QPT), we
propose and numerically investigate a mechanism that uses LZS interference to populate the first excited state, which in turn allows to avoid slow tunneling at the first-order QPT. Our analysis of a working principle of diabatic schedules provides an intriguing and intuitive physical explanation of potential advantages of diabatic quantum annealing over its adiabatic counter-part. Ultimately, our results pave the way towards designing algorithms that explicitly utilize LZS interference in diabatic quantum annealing.