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arXiv · 2409.11571

Monte Carlo Methods in the Manifold of Hartree-Fock-Bogoliubov Wave Functions

Ettore Vitali·Peter Rosenberg·Shiwei Zhang
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Abstract

We explore the possibility to implement random walks in the manifold of Hartree-Fock-Bogoliubov wave functions. The goal is to extend state-of-the-art quantum Monte Carlo approaches, in particular the constrained-path auxiliary-field quantum Monte Carlo technique, to systems where finite pairing order parameters or complex pairing mechanisms, e.g., Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) pairing or triplet pairing, may be expected. Leveraging the flexibility to define a vacuum state tailored to the physical problem, we discuss a method to use imaginary-time evolution of Hartree-Fock-Bogoliubov states to compute ground state correlations, extending beyond situations spanned by current formalisms. Illustrative examples are provided.

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Ettore Vitali, Peter Rosenberg, Shiwei Zhang. 2024-09-17. Monte Carlo Methods in the Manifold of Hartree-Fock-Bogoliubov Wave Functions. https://arxiv.org/abs/2409.11571

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