Towards quantum applications based on photonic entanglement

Anton Zeilinger

Shigeki Takeuchi

Quantum information science has recently attracted a lot of attention. Its applications include secure communication, quantum computation, quantum simulation, and quantum metrology. In these applications, photons are one of the most important physical quanta for their tolerance to decoherence. In this manuscript, we review the recent progress in single-photon/entangled-photon emitters and their applications: heralded single-photon sources using parametric downconversion and their application to quantum key distribution, highly indistinguishable heralded single-photon sources, fiber-coupled solid-state single-photon sources, and ultrabroadband-frequency entanglement generation.

G. Brida, Marco Genovese, C. Novero

Besides many interesting applications to the study of the foundations of quantum mechanics, entangled states are now assuming much relevance for some practical applications. In particular, we discuss the use of two-photon entangled states produced in parametric down conversion for absolute quantum efficiency calibration of photodetectors, in the photon counting regime.

Kyo Inoue, Hiroki Takesue

Quantum entangled photons, which are usually created via optical nonlinearity, have a unique correlation between them. This paper describes entangled-photon generation using spontaneous four-wave mixing in fiber and its application to quantum cryptography.

Gregor Weihs