Competitive algorithms for calculating the ground state properties of Bose-Fermi mixtures

In this work we define, analyze, and compare different numerical schemes that can be used to study the ground state properties of Bose-Fermi systems, such as mixtures of different atomic species under external forces or self-bound quantum droplets. The bosonic atoms are assumed to be condensed and are described by the generalized Gross-Pitaevskii equation. The fermionic atoms, on the other hand, are treated individually, and each atom is associated with a wave function whose evolution follows the Hartree-Fock equation. We solve such a formulated set of equations using a variety of methods, including those based on adiabatic switching of interactions and the imaginary time propagation technique combined with the Gram-Schmidt orthonormalization or the diagonalization of the Hamiltonian matrix. We show how different algorithms compete at the numerical level by studying the mixture in the range of parameters covering the formation of self-bound quantum Bose-Fermi droplets. • Split operator method for the system of condensed bosons and degenerate fermions. • Ground state of the Bose-Fermi mixture by the Gram-Schmidt orthonormalization. • Ground state of the Bose-Fermi mixture by diagonalizing the Hamiltonian matrix. • Formation of Bose-Fermi droplets using the split operator method.