Observation of the phononic Lamb shift with a synthetic vacuum

  title={Observation of the phononic Lamb shift with a synthetic vacuum},
  author={Timm Rentrop and A. Trautmann and F. A. Olivares and Fred Jendrzejewski and Andreas Komnik and Markus K. Oberthaler},
  journal={arXiv: Quantum Gases},
The quantum vacuum fundamentally alters the properties of embedded particles. In contrast to classical empty space, it allows for creation and annihilation of excitations. For trapped particles this leads to a change in the energy spectrum, known as Lamb shift. Here, we engineer a synthetic vacuum building on the unique properties of ultracold atomic gas mixtures. This system makes it possible to combine high-precision spectroscopy with the ability of switching between empty space and quantum… 

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