Influence of Backflow on Roton Quantum Evaporation
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چکیده
Sobnack et al. recently investigated theoretically the effect of roton backflow on the scattering of atoms, rotons, and phonons at the free surface of superfluid helium-II at T = 0K. They treated backflow semi-phenomenologically by modifying the potential in their earlier theory. This paper compares their predictions for the wave-vector dependence of roton quantum-evaporation with time-resolved experiments. It is found that the wave-vector dependence observed in the experiments is much less extreme than was predicted, and we discuss the implications of this result for this type of theory. PACS numbers: 67.40.Db, 68.45.Da, 67.40.-w
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تاریخ انتشار 2001