Entanglement and nonclassicality of twin beams containing noise

Using the characteristic function of a twin beam composed of both paired and noise components we derive the corresponding statistical operator in the Fock-state basis. Applying the Peres-Horodecki criterion for a partially transposed statistical operator, we determine the negativity of the twin beam to quantify entanglement. In parallel, nonclassicality of the twin beam is quantified by nonclassical depth which is the acceptable amount of noise photons that preserves non-classicality manifested by negative values of the Glauber-Sudarshan quasi-probability function. The connection between entanglement and non-classicality is discussed considering the noise present either in one or both fields constituting the twin beam. Also the state of dimensionality via the Schmidt number as well as von Neumann entropy of the twin beam is analyzed.