EACN Workshop 2021 | Extending links in quantum networks – an overview... (Christoph Becher) скачать в хорошем качестве

EACN Workshop 2021 | Extending links in quantum networks – an overview... (Christoph Becher)

Extending links in quantum networks – an overview on the research network Q.Link.X Quantum networks, i.e. local nodes consisting of stationary quantum bits able to process and store quantum information connected by “flying” qubits suited to transfer this information, are at the heart of concepts for long-range secure quantum communication and distributed quantum computing or quantum sensing. The main obstacle in establishing networks over large distances is the inherent loss of transmission channels, in particular for networks based on an infrastructure of optical fibers. The most feasible and promising route towards long distance quantum communication without sacrificing the physical security based on quantum mechanical concepts is based on quantum repeaters [1] to distribute entangled states to remote communication partners. The German research network “Quantum Links extended – Q.Link.X” investigates a bottom-up approach to realizing basic elements of fiber-based quantum repeaters (QR). The basic elements are QR-segments, i.e. heralded entanglement distribution between two nodes, and QR-cells, i.e. a node comprising two qubits sending out photons entangled with one of the qubits, respectively, and gate operations between the qubits to perform a Bell-state measurement, realizing a “single sequential quantum repeater” scheme [2]. The combination of QR-segments and QR-cells then allows for scaling up the quantum links. Q.Link.X investigates three different hardware platforms to realize these elements, i.e. trapped neutral atoms and ions, semiconductor quantum dots and color centers in diamond. The talk will present the basic concepts and an overview on recent experimental achievements in Q.Link.X. References [1] H.-J. Briegel et al., Phys. Rev. Lett. 81, 5932 (1998). DOI: 10.1103/PhysRevLett.81.5932 [2] D. Luong et al., Appl. Phys. B 122, 96 (2016). DOI: 10.1007/s00340-016-6373-4 ▶ EACN Workshop: https://www.mcqst.de/eacn-workshop MCQST ▶ Website: https://www.mcqst.de​​​​​ ▶ Twitter:   / mcqst_cluster   ▶ LinkedIn:   / mcqst​