Recent progress in cooling and trapping of polarized clouds of chromium $^{ 52}Cr$, dysprosium $^{ 164}Dy$ and erbium $^{ 168}Er$ opens a road-map to quantum systems where shapes of inter-particle interactions can be customized. The main purpose of this work is to get a deeper insight on a role which the overall shape of the inter-particle interaction plays in a context of trapped ultra-cold bosons. We show that strong inter-particle repulsion inevitably leads to multi-hump fragmentation of the ground state. The fragmentation phenomenon is universal -- it takes place in traps of different dimensionality and topologies and for very broad classes of repulsive inter-particle potentials. The physics behind is identified and explained.
Categories: cond-mat.quant-gas quant-ph