New prospects and techniques for matter wave interferometry with ions
Author(s): G. Schütz, A. Rembold, A. Pooch, A. Rauschenbeutel, I.-S. Hwang, A. Stibor
Journal: arXiv: physics.optics
DOI Number: --
Link: Link to publication
We present new developments and potential applications for the first ion-interferometer realized by Maier et al. [1-4], that verified at the end of the last century biprism interference and diffraction of 3 keV helium ions. The design of the setup is based on a coherent field emission source, an electrostatically charged biprism wire as a beam splitter and a multi-channel plate detector. However, due to deficiencies of the coherent ion source in the setup of Maier et al., the interference signal was low, therefore long integration times had to be accepted. In addition, the production of a significant uncharged particle radiation produced a high background intensity. The rest of the instrument proved to have excellent electron and ion optical properties and a high mechanical and electrical stability. Here we describe in detail the original setup and the major innovations to overcome the deficiencies. We introduce a novel single-atom metal tip  as a stable, coherent and monochromatic field emission ion source with high brightness. Furthermore, a custom-built fiber pulling rig is used for fabricating silica nanowires with a homogeneous and reproducible diameter in the 100 nm range. These silica nanowires are then gold coated in order to realize the biprism beam splitter. The application of a delay line detector allows for a spatial as well as temporal resolution of the ion signal. Compared to neutral atoms and point-like electrons, ions combine the properties charge and inner structure. This feature together with the high expected ion signal due to the new source, opens up possibilities for novel quantum optical experiments concerning the dependence of the inner particle structure in the Aharonov-Bohm effect. Additionally, with such an ion interferometer the first direct proof of the electrostatic Aharonov-Bohm effect comes into reach of current technical possibilities.