Characterization of Spectral Entanglement of Spontaneous Parametric-Down Conversion Biphotons

Abstract

We verified operational approach based on direct measurement of entanglement degree for bipartite systems. In particular spectral distributions of single counts and coincidence for pure biphoton states generated by train of short pump pulses have been measured and entanglement quantifier calculated. The approach gives upper bound of entanglement stored in total biphoton states, which can reach extremely high value up to $10^4-10^5$.

References in corpus (7)

• Heralded Generation of Ultrafast Single Photons in Pure Quantum States
• Research on Hidden Variable Theories: a review of recent progresses
• Tomographic reconstruction of the single-photon Fock state by high-frequency homodyne detection
• Shaping the waveform of entangled photons
• Anisotropically high entanglement of biphotons generated in spontaneous parametric down conversion
• Dispersion spreading of biphotons in optical fibres and two-photon interference
• Control, measurement and propagation of entanglement in photon pairs generated through type-II parametric downconversion

Cited by in corpus (6)

• Generation of broadband spontaneous parametric fluorescence using multiple bulk nonlinear crystals
• Entanglement Witnesses and Measures for Bright Squeezed Vacuum
• Biphoton Spectrum Control
• Experimental observation of double-peak structure of coincidence spectra in ultra-fast Spontaneous Parametric Down Conversion
• A note on Schmidt-number witnesses based on symmetric measurements
• Advances in Position-Momentum Entanglement: A Versatile Tool for Quantum Technologies