Abstract
We describe a measurement of the transmission probability of atoms through a freely suspended slab of superfluid at low temperatures. In our experiment the slab is realized by using an array of parallel cylindrical holes of diameter in a glass disc of thickness . By controlling the chemical potential, the holes can be made to fill or empty with liquid, and the surface curvature varied. We have measured the transmission of atom beams, generated by a thin-film heater and detected with a sensitive bolometer, through this structure. The results show that the dominant transmission channel is atom– roton–atom with a probability and that rotons can undergo total internal reflection at the free liquid surfaces.
- Received 16 April 2003
DOI:https://doi.org/10.1103/PhysRevLett.91.085301
©2003 American Physical Society