Quantum and classical correlations of intense beams of light investigated via joint photodetection

Agliati, Andrea; Bondani, Maria; Andreoni, Alessandra; Cillis, Giovanni De; Paris, Matteo G. A.

doi:10.1088/1464-4266/7/12/031

Cited by 68 publications

(53 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For the data in the inset, we obtained a value of the correlation coefficient Γ(0) = 0.984 that indicates a high degree of the correlation. As we emphasized in [19], a high value of correlation is not sufficient to discriminate between quantum and classical correlations since in both cases Γ(0) → 1. An explicit marker of nonclassicality can be obtained by considering the distribution of the photon-count difference P (d), which is plotted in Fig.…”

Section: Sub-shot-noise Correlationsmentioning

confidence: 95%

Sub-shot-noise photon-number correlation in a mesoscopic twin beam of light

Bondani¹,

et al. 2007

Self Cite

View full text Add to dashboard Cite

We demonstrate sub-shot-noise photon-number correlations in a (temporal) multimode mesoscopic (∼ 10 3 detected photons) twin-beam produced by ps-pulsed spontaneous non-degenerate parametric downconversion. We have separately detected the signal and idler distributions of photons collected in twin coherence areas and found that the variance of the photon-count difference goes below the shot-noise limit by 3.25 dB. The number of temporal modes contained in the twin-beam, as well as the size of the twin coherence areas, depends on the pump intensity. Our scheme is based on spontaneous downconversion and thus does not suffer from limitations due to the finite gain of the parametric process. Twin-beams are also used to demonstrate the conditional preparation of a nonclassical (sub-Poissonian) state.

show abstract

Section: Sub-shot-noise Correlationsmentioning

confidence: 95%

Sub-shot-noise photon-number correlation in a mesoscopic twin beam of light

Bondani¹,

et al. 2007

Self Cite

View full text Add to dashboard Cite

show abstract

“…2 we plot the experimental data (full circles) obtained by evaluating g jk up to the fourth order together with the theoretical expectations (line+open circles) for a multimode TWB calculated according to Eqs. (4) by using the values of m , µ and η as directly obtained from the experimental data [15,18]. Since the values m 1 and m 2 are slightly different, in Fig.…”

mentioning

confidence: 99%

Measuring high-order photon-number correlations in experiments with multimode pulsed quantum states

2012

Self Cite

View full text Add to dashboard Cite

We implement a direct detection scheme based on hybrid photodetectors to experimentally investigate high-order correlations for detected photons by means of quantities that can be experimentally accessed. We show their usefulness in fully characterizing a multimode twin-beam state in comparison with classical states and, in particular, we introduce a nonclassicality criterion based on a simple linear combination of high-order correlation functions. Our scheme is self-consistent, allowing the estimation of all the involved parameters (quantum efficiency, number of modes and average energy) directly from the same experimental data. Results are in very good agreement with theory, thus suggesting the exploitation of our scheme for reliable state characterization in quantum technology.

show abstract

“…The signal is sampled around this sideband to avoid the classical noise present in the frequency band around the carrier [13]. Ten digitized samples correspond to the photocurrent at this sideband generated by photons impinging on the photodiode for 1 s. This photodetection can be modeled by the positive operator-valued measure^J m jJ; mihJ; mj, so that w J m Tr%^J m is the probability of detecting n H J m photons in the horizontal mode and simultaneously n V J ÿ m photons in the vertical one [14].…”

mentioning

confidence: 99%