Entanglement and Quantum Information

Zeilinger

Sylvain Borderieux, Arnaud Coatanhay, Ali Khenchaf

The quantum illumination radar uses pairs of entangled photons to enhance the detection sensitivity of a reflecting target.In this paper, we worked on a quantum illumination radar using a pair of entangled photons in polarization in the microwave frequency range in the atmosphere.We studied the quantum information evolution modeling the propagation of a photon in the atmosphere while building two binary decision strategies for the QI radar.We focused on the quantum information evolution showing that the quantum discord representing quantum correlations beyond entanglement could represent an interesting resource to explore for the subject of quantum radar.In addition, we made an approximative estimation of the entanglement survival distance in the atmosphere.Results showed that an optimization should be found to favour the survival of quantum correlations or the signal-to-noise ratios calculated with the binary decision strategy.

Andrew G. White, Daniel F. V. James, William J. Munro +1 more

Yifan Wang

Quantum information is a cutting-edge technology that has numerous applications. It mainly makes usage of some quantum entanglement characteristics and uses the quantum entangled state as a carrier for information transfer. Therefore, compared to traditional information, quantum information has excellent features, e.g., stronger security and reduced susceptibility to interference. This article introduces the definition, concept, characteristics and history of quantum entanglement and quantum information. To be specific, this study lists the applications of quantum entanglement in communication and radar. In addition, it gives an outlook on the future function of quantum entanglement in quantum information based on the advantages and disadvantages of quantum entanglement. Contemporarily, the field of physics is rapidly advancing in both quantum entanglement and quantum information, and there have also been significant technological advancements. In experiments, scientists have been able to extend the transmission distance of quantum information to great distances. At the same time, scholars are looking for ways to minimise the interference of quantum information during transmission. In constant exploration and experimentation, the experimental results have inspired scientists to explore the deeper realms of quantum information.

Sébastien Tanzilli, Wolfgang Tittel, Hugo Zbinden +3 more

The experiment performed aims to transfer the quantum information (QI) carried by "telecom photons" at 1310 nm to "visible photons". This is a necessary step to realize a quantum interface between photons and atoms. To this end, in the most general case, entanglement produced by parametric down-conversion is preserved when submitting one photon out of an entangled pair to a wavelength up-conversion process (i.e. sum frequency generation SFG) in a nonlinear crystal.

Carlton M. Caves