Quantum computing description of strongly interacting atomic nuclei: challenges and opportunities

Atomic nuclei can exhibit shape coexistence and multireference physics that enters in their ground states, and accurately capturing the ensuing correlations and entanglement is challenging. We address this problem by applying single-reference coupled-cluster theory based on spherical and deformed reference states and the tailored coupled-cluster method. The latter combines configuration interactions to capture static correlations with coupled-cluster theory for dynamic correlations. We compute the atomic nuclei $^{12}\mathrm{C}, ^{28}\mathrm{Si}$ , and $^{56}\mathrm{Ni}$ and find that the tailored coupled-cluster method and the single-reference approach based on a deformed Hartree-Fock state yield the most accurate results.Atomic nuclei can exhibit shape coexistence and multireference physics that enters in their ground states, and accurately capturing the ensuing correlations and entanglement is challenging. We address this problem by applying single-reference coupled-cluster theory based on spherical and deformed reference states and the tailored coupled-cluster method. The latter combines configuration interactions to capture static correlations with coupled-cluster theory for dynamic correlations. We compute the atomic nuclei $^{12}\mathrm{C}, ^{28}\mathrm{Si}$, and $^{56}\mathrm{Ni}$ and find that the tailored coupled-cluster method and the single-reference approach based on a deformed Hartree-Fock state yield the most accurate results.

arXiv:2305.07577Physical Review CJul 6, 202311 citations

Response of strongly coupled fermions on classical and quantum computers

J. Novák, Manqoba Q. Hlatshwayo, Елена Литвинова

Studying the response of quantum systems is essential for gaining deeper insights into the fundamental nature of matter and its behavior in diverse physical contexts. Computation of nuclear response is critical for many applications, but its spectroscopically accurate description in medium-heavy nuclei in wide energy ranges remains particularly challenging because of the complex nature of nuclear quantum states in the high-level-density regime. Herein, we push the limits of configuration complexity in the classical computation of the nuclear response and present an algorithm with a quantum benefit for treating complex configurations. The classical computational method of approaching spectroscopic accuracy is implemented for medium-heavy nuclei and pioneered for the dipole response of 120Sn, while the quantum algorithm reaching the exact solution is realized for the Lipkin Hamiltonian to unravel the emergence of collectivity at strong coupling.Studying the response of quantum systems is essential for gaining deeper insights into the fundamental nature of matter and its behavior in diverse physical contexts. Computation of nuclear response is critical for many applications, but its spectroscopically accurate description in medium-heavy nuclei in wide energy ranges remains particularly challenging because of the complex nature of nuclear quantum states in the high-level-density regime. Herein, we push the limits of configuration complexity in the classical computation of the nuclear response and present an algorithm with a quantum benefit for treating complex configurations. The classical computational method of approaching spectroscopic accuracy is implemented for medium-heavy nuclei and pioneered for the dipole response of 120Sn, while the quantum algorithm reaching the exact solution is realized for the Lipkin Hamiltonian to unravel the emergence of collectivity at strong coupling.

arXiv:2405.02255May 3, 20240 citations

Quantum computing for nuclear physics: status and expectations

Natalie Kloco

Bulletin of the American Physical SocietyOct 27, 20180 citations

Wavefunction matching for solving quantum many-body problems

Serdar Elhatisari, Lukas Bovermann, Yuan-Zhuo Ma +15 more

Abstract Ab initio calculations have an essential role in our fundamental understanding of quantum many-body systems across many subfields, from strongly correlated fermions 1–3 to quantum chemistry 4–6 and from atomic and molecular systems 7–9 to nuclear physics 10–14 . One of the primary challenges is to perform accurate calculations for systems where the interactions may be complicated and difficult for the chosen computational method to handle. Here we address the problem by introducing an approach called wavefunction matching. Wavefunction matching transforms the interaction between particles so that the wavefunctions up to some finite range match that of an easily computable interaction. This allows for calculations of systems that would otherwise be impossible owing to problems such as Monte Carlo sign cancellations. We apply the method to lattice Monte Carlo simulations 15,16 of light nuclei, medium-mass nuclei, neutron matter and nuclear matter. We use high-fidelity chiral effective field theory interactions 17,18 and find good agreement with empirical data. These results are accompanied by insights on the nuclear interactions that may help to resolve long-standing challenges in accurately reproducing nuclear binding energies, charge radii and nuclear-matter saturation in ab initio calculations 19,20 .Abstract Ab initio calculations have an essential role in our fundamental understanding of quantum many-body systems across many subfields, from strongly correlated fermions 1–3 to quantum chemistry 4–6 and from atomic and molecular systems 7–9 to nuclear physics 10–14 . One of the primary challenges is to perform accurate calculations for systems where the interactions may be complicated and difficult for the chosen computational method to handle. Here we address the problem by introducing an approach called wavefunction matching. Wavefunction matching transforms the interaction between particles so that the wavefunctions up to some finite range match that of an easily computable interaction. This allows for calculations of systems that would otherwise be impossible owing to problems such as Monte Carlo sign cancellations. We apply the method to lattice Monte Carlo simulations 15,16 of light nuclei, medium-mass nuclei, neutron matter and nuclear matter. We use high-fidelity chiral effective field theory interactions 17,18 and find good agreement with empirical data. These results are accompanied by insights on the nuclear interactions that may help to resolve long-standing challenges in accurately reproducing nuclear binding energies, charge radii and nuclear-matter saturation in ab initio calculations 19,20 .

NatureMay 15, 202462 citations

^{12}\mathrm{C}, ^{28}\mathrm{Si}

, and

^{56}\mathrm{Ni}

and find that the tailored coupled-cluster method and the single-reference approach based on a deformed Hartree-Fock state yield the most accurate results.