相关论文: Compact and stable source of polarization-entangle…
The thorough characterization of entangled-photon sources is vital for their optimal use in quantum communication. However, this task is not trivial at telecommunication wavelengths. While cameras and spectrometers are well developed for…
Entanglement-based QKD protocols require robust and stable photon pair sources in terms of high heralding efficiencies or photon pair generation rates even under harsh environmental conditions, e.g. when operated in the field. In this…
Flat-optics platforms offer new opportunities for the generation of entangled photons by relaxing traditional phase-matching constraints, enabling the use of a broader range of nonlinear materials. Among these, gallium arsenide and aluminum…
Spectrally correlated photon pairs can be used to improve performance of long range fiber based quantum communication protocols. We present a source based on spontaneous parametric down-conversion producing polarization entangled photons…
We experimentally demonstrated entanglement extraction scheme by using photons at the telecommunication band for optical-fiber-based quantum communications. We generated two pairs of non-degenerate polarization entangled photons at 780~nm…
Performing reliable measurements in optical metrology, such as those needed in ellipsometry, requires a calibrated source and detector, or a well-characterized reference sample. We present a novel interferometric technique to perform…
We report on the generation of indistinguishable photon pairs at telecom wavelengths based on a type-II parametric down conversion process in a periodically poled potassium titanyl phosphate (PPKTP) crystal. The phase matching, pump laser…
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 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…
Entangled photon sources (EPS) are essential for quantum science and technology. Despite advancements in integrated optical platforms like thin-film lithium niobate, a scalable, high-performance, chip-scale EPS has remained elusive. We…
Top-performance sources of photonic entanglement are an indispensable resource for many applications in quantum communication, most notably quantum key distribution. However, up to now, no source has been shown to simultaneously exhibit the…
Entangled photon pair sources based on bulk optics are approaching optimal design and implementation, with high state fidelities, spectral purities and heralding efficiencies, but generally low brightness. Integrated entanglement sources,…
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…
Quantum state distribution over vast distances is essential for global-scale quantum networks and fundamental test of quantum physics at space scale. While satellite platforms have demonstrated thousand-kilometer entanglement distribution,…
We report the fusion of photons from two independent photonic crystal fiber sources into polarization entangled states using a fiber-based polarizing beam splitter. We achieve fidelities of up to F = 0.74 $\pm$ 0.01 with respect to 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…
Quantum entanglement is a key resource in quantum information science, playing an essential role in quantum key distribution (QKD), quantum networks, and distributed quantum computing. However, practical applications require techniques…
We report measurements of two-photon interference using a cw-pumped type-II spontaneous parametric down-conversion source based on a multimode perodically poled potassium titanyl phosphate waveguide. We have used the recently demonstrated…
Quantum entanglement is a fundamental resource for emerging quantum technologies, enabling secure communication and enhanced sensing. For decades, generating polarization entangled states has been mainly achieved using bulk crystals with…
Entangled photon pairs are key elements in quantum communication and quantum cryptography. State-of-the-art sources of entangled photons are mainly based on parametric down-conversion from nonlinear crystals, which is probabilistic in…