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تسجيل مستخدم جديدSpectral correlation in down-converted photon pairs at telecom wavelength
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Sources of photon pairs based on the spontaneous parametric down conversion process are commonly used for long distance quantum communication. The key feature for improving the range of transmission is engineering their spectral properties. Following two experimental papers [Opt. Lett., 38, 697 (2013)] and [Opt. Lett., 39, 1481 (2014)] we analytically and numerically analyze the characteristics of a source. It is based on a $beta$-barium borate (BBO) crystal cut for type II phase matching at the degenerated frequencies 755 nm $rightarrow$ 1550 nm + 1550 nm. Our analysis shows a way for full control of spectral correlation within a fiber-coupled photon pair simultaneously with optimal brightness.
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The frequency correlation (or decorrelation) of photon pairs is of great importance in long-range quantum communications and photonic quantum computing. We experimentally characterize a spontaneous parametric down conversion (SPDC) source, based on a
Beta-Barium Borate (BBO) crystal cut for type-II phase matching at 1550 nm which emits photons with the positive or no spectral correlations. Our system employs a carefully designed detection method exploiting two InGaAs detectors.
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 without spec
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We demonstrate a hybrid approach to the generation of photon pairs of a short wavelength with high brightness, by combining parametric down-conversion (SPDC) and up-conversion techniques. Photon pairs were generated at the wavelength of 1550 nm via S
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