Detecting topological entanglement entropy in a lattice of quantum harmonic oscillators

  title={Detecting topological entanglement entropy in a lattice of quantum harmonic oscillators},
  author={Tommaso F. Demarie and Trond Linjordet and Nicolas C. Menicucci and Gavin K. Brennen},
  journal={New Journal of Physics},
The Kitaev surface code model is the most studied example of a topologically ordered phase and typically involves four-spin interactions on a two-dimensional surface. A universal signature of this phase is topological entanglement entropy (TEE), but due to low signal to noise, it is extremely difficult to observe in these systems, and one usually resorts to measuring anyonic statistics of excitations or non-local string operators to reveal the order. We describe a continuous-variable analog to… 
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