Advancements in Quantum Computing for Neutron-Proton Pairing Analysis

Recent research has utilized the ADAPT-VQE approach to address the neutron-proton pairing problem in atomic nuclei. This method is recognized as a powerful variational technique for iteratively determining the ground state of many-body systems. The study, authored by Jing Zhang, Denis Lacroix, and Yann Beaujeault-Taudiere, explores three different pools of operators that may disrupt certain symmetries of the Hamiltonian during the optimization process. Notably, the researchers found that breaking some symmetries could enhance the convergence speed towards the ground state. However, they dismissed the use of operators that would explicitly break the total particle number due to their uncontrollable nature during optimization.

The findings indicate that as the number of parameters in the ansatz increases, the iterative optimization can become complex, leading to potential stagnation at higher energy levels instead of reaching the ground state. To mitigate this issue, the authors proposed several techniques to improve convergence, with two methods proving particularly effective: one utilizing an embedding technique and the other employing a randomized initial state preparation. The study concludes that the ADAPT-VQE method, when complemented by these techniques, offers a highly accurate description of neutron-proton pairing and can outperform traditional methods that break particle number symmetry and attempt to restore it later.

This research is significant as it enhances our understanding of nuclear interactions and could have implications for future developments in quantum computing and nuclear physics. The full paper can be accessed at arXiv:2408.17294.