2024/03/08 by Mario Sánchez Sánchez, Sánchez, M. S., J. A. Oller +3
Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #Quantum Mechanics and Non-Hermitian Physics #Quantum, superfluid, helium dynamics
paper · pdf · doi:10.48550/arxiv.2403.05486
We study a family of separable potentials with and without added contact interactions by solving the associated Lippmann-Schwinger equation with two coupled partial waves. The matching of the resulting amplitude matrix with the effective-range expansion is studied in detail. When a counterterm is included in the potential we also carefully discuss its renormalization. Next, we use the matrix N/D method and study whether the amplitude matrices from the potentials considered admit an N/D representation in matrix form. As a novel result we show that it is typically not possible to find such matrix representation for the coupled partial-wave case. However, a separate N/D representation for each coupled partial wave, a valid option known in the literature, is explicitly implemented and numerically solved in cases where the matrix N/D method is unavailable.