Witnessing Wigner Negativity

  title={Witnessing Wigner Negativity},
  author={Ulysse Chabaud and Pierre-Emmanuel Emeriau and Fr{\'e}d{\'e}ric Grosshans},
Negativity of the Wigner function is arguably one of the most striking non-classical features of quantum states. Beyond its fundamental relevance, it is also a necessary resource for quantum speedup with continuous variables. As quantum technologies emerge, the need to identify and characterize the resources which provide an advantage over existing classical technologies becomes more pressing. Here we derive witnesses for Wigner negativity of single mode and multimode quantum states, based on… Expand

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