Entanglement Dimensionality of Continuous Variable States From Phase-Space Quasi-Probabilities
The work introduces new Schmidt number witnesses for continuous-variable (CV) systems by directly using correlations and covariances of phase-space observables, accessible via measurements like characteristic or Wigner functions. This direct CV approach is shown to be more robust and versatile than first discretizing the system and using standard discrete variable techniques, allowing for better characterization of entanglement dimensionality.