Three-body and Coulomb interactions in a quasi-two-dimensional dipolar Bose-condensed gas

Collective excitation of quantum droplet with different ranges of the interaction of Pöschl-Teller potential

“…The PT interactions have a distinct effect compared to other types of longrange interactions (i.e., dipole-dipole and coulomb interactions), and there is no singularity in the PT potential. In the excitation spectrum, we found that the phonon mode stiffens [40] with a stronger and longer range of interactions, whereas studies on dipolar bose gas suggest there are no significant changes in the phonon mode with the dipolar interaction strengths [58], and for the charged bose gas [59], the sound velocity increases (i.e., phonon mode energy increases) with increasing coulomb interaction for fixed dipolar strengths. In contrast to their study [58,59], we also found an interaction range and strength-dependent gap in the lower momentum region (k = 0).…”

“…We found that the roton in the spectra became more prominent with increasing strengths and ranges, whereas studies on dipolar gas suggest that the roton mode stiffens with increasing dipolar strengths, and the increasing coulomb interaction also stiffens the roton [58,59]. The roton mode appears due to long-range interaction and disappears when PT interaction tends to become a delta function-type interaction.…”