Diminished quantum depletion and correlated droplets in one-dimensional dipolar Bose gas

We investigate the formation of self-bound states in a one-dimensional dipolar Bose gas under the influence of both strong short-range repulsive and strong nonlocal attractive interactions. While conventional methods such as the Bogoliubov-de Gennes (BdG) method typically fail in regimes with strong interactions due to significant quantum depletion, we reveal a particular scenario where the interplay of these strong interactions significantly mitigates quantum depletion, thus restoring the applicability of the BdG method. Remarkably, this restoration occurs even though the system exhibits pronounced antibunching, a feature usually linked with strongly correlated systems. By comparing our BdG results with exact ab initio calculations, we confirm the accuracy of the BdG approach in predicting the ground-state energy and correlation functions under these conditions. Furthermore, we demonstrate that adjusting the polarization direction of the dipoles allows for a tunable transition between a strongly interacting regime and the different balanced regime explored in this research.