Beilstein Journal of Nanotechnology

Dynamic of cold-atom tips in anharmonic potentials

Tobias Menold, Peter Federsel, Carola Rogulj, Hendrik Hölscher, József Fortágh, Andreas Günther

Published Oct 31, 2016• 2 citations

Abstract

Background:Understanding the dynamics of ultracold quantum gases in an anharmonic potential is essential for applications in the new field of cold-atom scanning probe microscopy. Therein, cold atomic ensembles are used as sensitive probe tips to investigate nanostructured surfaces and surface-near potentials, which typically cause anharmonic tip motion. Results:Besides a theoretical description of this anharmonic tip motion, we introduce a novel method for detecting the cold-atom tip dynamics in situ and real time. In agreement with theory, the first measurements show that particle interactions and anharmonic motion have a significant impact on the tip dynamics. Conclusion:Our findings will be crucial for the realization of high-sensitivity force spectroscopy with cold-atom tips and could possibly allow for the development of advanced spectroscopic techniques such as Q-control.

DOI: 10.3762/bjnano.7.148

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