Excitation spectra of a 3He impurity on 4He clusters -: art. no. 023206

The diffusion Monte Carlo technique is used to calculate and analyze the excitation spectrum of a single He-3 atom bound to a cluster with N He-4 atoms, with the aim of establishing the most adequate filling ordering of single-fermion orbits to the mixed clusters with a large number of He-3 atoms. The resulting ordering looks like the rotational spectrum of a diatomic molecule, being classified only by the angular momentum of the level, although vibrational-like excitations appear at higher energies for sufficiently large N.