Related papers: Bright entangled photon source without stringent c…
The ability to engineer pairs of entangled photons is essential to quantum information science, and generating these states using spontaneous parametric down-conversion (SPDC) in nano- and micrometer-scale materials offers numerous…
Using the process of spontaneous parametric down conversion in a novel two-crystal geometry, one can generate a source of polarization-entangled photon pairs which is orders of magnitude brighter than previous sources. We have measured a…
We present a compact, automated, high-brightness entangled photon source capable of generating all four Bell states with high fidelity. The system utilizes a type-0 quasi-phase-matched PPKTP crystal embedded within a polarization Sagnac…
A quantum system composed of two or more subsystems can be in an entangled state, i.e. a state in which the properties of the global system are well defined but the properties of each subsystem are not. Entanglement is at the heart of…
Photon entanglement is an important state of light that is at the basis of many protocols in photonic quantum technologies, from quantum computing, to simulation and sensing. The capability to generate entangled photons in integrated…
We demonstrate a wavelength-tunable, fiber-coupled source of polarization-entangled photons with extremely high spectral brightness and quality of entanglement. Using a 25 mm PPKTP crystal inside a polarization Sagnac interferometer we…
We designed and implemented a novel combination of a Sagnac-interferometer with a Mach-Zehnder interferometer for a source of polarization-entangled photons. The new versatile configuration does not require multi-wavelength polarization…
Spontaneous parametric down-conversion (SPDC) is a reliable platform for entanglement generation. Routinely, a coherent laser beam is an essential prerequisite for pumping the nonlinear crystal. Here we break this barrier to generate…
A bi-photon polarization-frequency entanglement source was realized by shaping the phase-matching function of a poled KTP crystal. It provides a simple method to achieve either polarization or spectral entanglement in a simple collinear…
Entangled photon pairs are essential for quantum communication technology. They can be generated on-demand by semiconductor quantum dots, but several mechanisms are known to reduce the degree of entanglement. While some obstacles like the…
We present a tunable, frequency-stabilized, narrow-bandwidth source of frequency-degenerate, entangled photon pairs. The source is based on spontaneous parametric downconversion (SPDC) in periodically-poled KTiOPO4 (PPKTP). Its wavelength…
We demonstrate a bright, narrowband, compact, quasi-phase-matched single-crystal source generating path-polarization-entangled photon pairs at 810 nm and 1550 nm at a maximum rate of 3 Mcounts/(s THz mW) after coupling to single-mode fiber,…
A workflow for evaluation of entanglement source quality is proposed. Based on quantum state density matrices obtained from theoretical models and experimental data, we make an estimate of a potential performance of a quantum entanglement…
We report on the experimental generation of an entangled state with a spectrally pure heralded single-photon state and a weak coherent state. By choosing group-velocity matching in the nonlinear crystal, our system for producing entangled…
Entangled photons are crucial resources for quantum information processing. Here, we present an ultrabright polarization-entangled photon source based on a periodically poled lithium niobate waveguide designed for practical quantum…
We demonstrate a new generation mechanism for polarisation- and colour-entangled photon pairs. In our approach we tailor the phase-matching of a periodically poled KTP crystal such that two downconversion processes take place…
Deterministic sources of high-fidelity entangled qubit pairs encoded in the dual-rail photonic basis, i.e., presence of a single photon in one of two orthogonal modes, are a key enabling technology of many applications of quantum…
We report an efficient energy-time entangled photon-pair source based on four-wave mixing in a CMOS-compatible silicon photonics ring resonator. Thanks to suitable optimization, the source shows a large spectral brightness of 400\,pairs of…
We report the demonstration of a bulk, intrinsically phase-stable source of polarization- and time-energy-entangled photon pairs at 810nm and 1550nm, directly coupled into single-mode optical fibers. This highly non-degenerate wavelength…
Particle entanglement is a fundamental resource upon which are based many quantum technologies. However, the up-to-now best sources of entangled photons rely on parametric down-conversion processes, which are optimal only at certain…