Related papers: Multi-photon, multi-mode polarization entanglement…
The need for spatial and spectral filtering in the generation of polarization entanglement is eliminated by combining two coherently-driven type-II spontaneous parametric downconverters. The resulting ultrabright source emits photon pairs…
Type-II Optical Parametric Oscillators are efficient sources of quadrature squeezed or polarization squeezed light, intensity correlated beams, and entangled light. We review here the different levels of quantum correlations and…
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 propose and theoretically analyze a new scheme for generating hyper-entangled photon pairs in a system of polaritons in coupled planar microcavities. Starting from a microscopic model, we evaluate the relevant parametric scattering…
We study broadband polarization entangled states generated within the line width of type-II Spontaneous Parametric Down Conversion (SPDC). Applying a complete quantum polarization tomography protocol at arbitrary combination of frequency…
We consider a photonic crystal (PC) doped with four-level atoms whose intermediate transition is coupled near-resonantly with a photonic band-gap edge. We show that two photons, each coupled to a different atomic transition in such atoms,…
We discuss both theoretically and experimentally elementary two-photon polarization entanglement localization after break of entanglement caused by linear coupling of environmental photon with one of the system photons. The localization of…
We present a scheme, based only on linear optics and standard photon detection, that allows to generate heralded multiphoton entangled states of arbitrary photon number from spontaneous parametric downconversion (PDC) in the weak…
The widespread availability of quantum entanglement with photons, in the guise of two-mode squeezed states, can be attributed to the phenomenon of parametric down-conversion. A reinterpretation of this effect with macroscopic mechanical…
Generating nonclassical states of photons such as polarization entangled states on a monolithic chip is a crucial step towards practical applications of optical quantum information processing such as quantum computing and quantum key…
We investigate the evolution of quantum correlations over the lifetime of a multi-photon state. Measurements reveal time-dependent oscillations of the entanglement fidelity for photon pairs created by a single semiconductor quantum dot. The…
A bipartite multiphoton entangled state is created through stimulated parametric down-conversion of strong laser pulses in a nonlinear crystal. It is shown how detectors that do not resolve photon number can be used to analyze such…
We formulate quantum optics to include frequency dependence in the modeling of optical networks. Entangled light pulses available for quantum cryptography are entangled not only in polarization but also, whether one wants it or not, in…
We experimentally investigate the properties of light generated by the sequential processes of spontaneous parametric downconversion followed by upconversion. By interfering the upconverted photons with the original pump light, we show that…
Extended phase-matching conditions for spontaneous parametric down-conversion are examined. By augmenting the conventional phase-matching conditions, they permit the creation of a class of frequency-entangled states that generalizes the…
We put forward a new highly efficient source of paired photons entangled in polarization with an ultra-large bandwidth. The photons are generated by means of a conveniently designed spontaneous parametric down-conversion process in a…
We describe a new experimental approach to probabilistic atom-photon (signal) entanglement. Two qubit states are encoded as orthogonal collective spin excitations of an unpolarized atomic ensemble. After a programmable delay, the atomic…
Hyperentanglement offers enhanced capacity for quantum information processing and communication protocols, especially in combination with robust high-dimensional degrees of freedom such as frequency-bin encoding. Here, we present a…
The heralded generation of entangled states is a long-standing goal in quantum information processing, because it is indispensable for a number of quantum protocols. Polarization entangled photon pairs are usually generated through…
Single-photon sources based on semiconductor quantum dots find several applications in quantum information processing due to their high single-photon indistinguishability, on-demand generation, and low multiphoton emission. In this context,…