Related papers: Two independent photon pairs versus four-photon en…
A simple experimental setup consisting of a spontaneous parametric down-conversion source and passive linear optics is proposed for conditional preparation of a maximally entangled polarization state of two photons. Successful preparation…
Entanglement of high dimensional states is becoming increasingly important for quantum communication and computing. The most common source of entangled photons is spontaneous parametric down conversion (SPDC), where the degree of frequency…
Hyperentangled photonic states - exhibiting nonclassical correlations in several degrees of freedom - offer improved performance of quantum optical communication and computation schemes. Experimentally, a hyperentanglement of…
We present an experimental characterization of the statistics of multiple photon pairs produced by spontaneous parametric down-conversion realized in a nonlinear medium pumped by high-energy ultrashort pulses from a regenerative amplifier.…
The process of spontaneous parametric down-conversion (SPDC) in nonlinear crystals makes it fairly easy to generate entangled photon states. It has been known for some time that the conversion efficiency can be improved by employing…
Besides many interesting application to the study of foundations of quantum mechanics, entangled state are now assuming a large relevance for some practical application. In particular, we discuss most recent results obtained in our…
We address the process of generation of the photon-number entangled states of light in the stimulated nonlinear parametric down conversion process and build the simple model describing the generation, not involving the traditional…
We report, for the first time, the generation of entangled photon pairs via type-0 spontaneous parametric down conversion in an ultra-thin wafer of lithium niobate in which momentum between the pump photon and daughter photons is not…
We study the chronocyclic character, i.e. the joint temporal and spectral properties, of the single-photon constituents of photon pairs generated by spontaneous parametric down conversion. In particular we study how single photon…
We show that the transfer of the angular spectrum of the pump beam to the two-photon state in spontaneous parametric down-conversion enables the generation of entangled Hermite-Gaussian modes. We derive an analytical expression for the…
We address the intrinsic multimode nature of the quantum state of light obtained by pulsed spontaneous parametric downconversion and develop a theoretical model based only on experimentally accessible quantities. We exploit the pairwise…
We demonstrate hybrid entanglement of photon pairs via the experimental violation of a Bell inequality with two different degrees of freedom (DOF), namely the path (linear momentum) of one photon and the polarization of the other photon.…
Quantum entanglement among multiple spatially separated particles is of fundamental interest, and can serve as central resources for studies in quantum nonlocality, quantum-to-classical transition, quantum error correction, and quantum…
The correlation properties of the pump field in spontaneous parametric down-conversion are crucial in determining the degree of entanglement of generated signal and idler photons. We find theoretically that continuous-variable entanglement…
We present an experimental realization of a two-photon conditional-phase switch, related to the ``$c$-$\phi $'' gate of quantum computation. This gate relies on quantum interference between photon pairs, generating entanglement between two…
Spontaneous parametric downconversion (SPDC) has been a key enabling technology in exploring quantum phenomena and their applications for decades. For instance, traditional SPDC, which splits a high energy pump photon into two lower energy…
A pulsed source of entangled photons is desirable for some applications. Yet, such a source has intrinsic problems arising from the simultaneous arrival of the signal and noise photons to the detectors. These problems are analyzed and…
One-photon and two-photon wavepackets of entangled two-photon states in spontaneous parametric down-conversion (SPDC) fields are calculated and measured experimentally. For type-II SPDC, measured one-photon and two-photon wavepackets agree…
Spontaneous parametric down-conversion (SPDC) is a widely used process to prepare entangled photon pairs. In SPDC, a second-order nonlinear crystal is pumped by a coherent laser beam to generate photon pairs. The photon pairs are usually…
Spectral and temporal coincidence and single-particle photon wave packets are described and their widths and durations are found. The degree of entanglement is characterized by the experimentally measurable parameter R defined as the ratio…