Shell structure in mixed 3 He - 4 He droplets
نویسندگان
چکیده
Due to the immiscibility of He into He at very low temperatures, mixed helium droplets consist of a core of He atoms coated by a He layer whose thickness depends on the number of atoms of each isotope. When these numbers are such that the centrifugal kinetic energy of the He atoms is small and can be considered as a perturbation to the mean-field energy, a novel shell structure arises, with magic numbers different from these of pure He droplets. If the outermost shell is not completely filled, the valence atoms align their spins up to the maximum value allowed by the Pauli principle.
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