Strongly dipolar Bose gases

Strongly dipolar Bose gases can form liquid droplets stabilized by quantum fluctuations. In a theoretical description of this phenomenon, the low-energy scattering amplitude is utilized as an effective potential. We show that for magnetic atoms corrections with respect to the Born approximation should be included in theoretical description. We derive a modified pseudopotential using a realistic interaction model. We then discuss the construction of the effective low-energy Hamiltonian for trapped systems with long-range interactions. Our results are relevant to recent experiments with erbium and dysprosium atoms.