We demonstrate a near-field Talbot-Lau interferometer for C-70 fullerene molecules. Such interferometers are particularly suitable for larger masses. Using three free-standing gold gratings of one micrometer period and a transversally incoherent but velocity-selected molecular beam, we achieve an interference fring  visibility of 40 % with high count rate. Both the high visibility and its velocity dependence are in good agreement with a quantum simulation that takes into account the van der Waals interaction of the molecules with the gratings and are in striking contrast to a classical moire model.

Klaus Hornberger, Stefan Uttenthaler, Bjoern Brezger, Lucia Hackermueller, Markus Arndt, Anton Zeilinger

Phys. Rev. Lett. 90, 160401 (2003)
arxiv.org/abs/quant-ph/0303093