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arXiv · 2310.01504

Auxiliary Field Quantum Monte Carlo for Dilute Neutrons on the Lattice

Ryan Curry·Jayani Dissanayake·Stefano Gandolfi·Alexandros Gezerlis
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Abstract

We employ constrained path Auxiliary Field Quantum Monte Carlo (AFQMC) in the pursuit of studying physical nuclear systems using a lattice formalism. Since AFQMC has been widely used in the study of condensed-matter systems such as the Hubbard model, we benchmark our method against published results for both one- and two-dimensional Hubbard model calculations. We then turn our attention to cold-atomic and nuclear systems. We use an onsite contact interaction that can be tuned in order to reproduce the known scattering length and effective range of a given interaction. Developing this machinery allows us to extend our calculations to study nuclear systems within a lattice formalism. We perform initial calculations for a range of nuclear systems from two- to few-body neutron systems.

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Ryan Curry, Jayani Dissanayake, Stefano Gandolfi, Alexandros Gezerlis. 2023-10-02. Auxiliary Field Quantum Monte Carlo for Dilute Neutrons on the Lattice. https://doi.org/10.1098/rsta.2023.0127

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