Ricerc@Sapienza

Quantum networks is a promising field of research which aims to the development of infrastructures devoted to the execution of quantum informational tasks, such as secure quantum communication and distributed quantum computing. A quantum network is made up of nodes, connected together through classical and quantum channels. Using photons for the encoding of information, quantum networks need single-photon sources as essential building blocks. A complete quantum network should be composed of many interconnected single-photon sources, allowing the full exploitation of complex quantum schemes.
In recent years important progresses have been made in the generation of single photons with quantum dots (QDs). The interest in this platform is due to the fact that they can produce on-demand single photons through quantized exciton recombinations. The advantage with respect to other on-demand single-photon sources, like single atoms, is that they do not require demanding cooling techniques.
The sharp absorption line of an atomic gas can be used as frequency reference in quantum optics experiments. This fact can be extremely useful in solving one of the major issues affecting QDs: each QD is different from the others, showing different energies for the emitted photons and thus reducing the indistinguishability, which is indeed essential for quantum communication and computation.
In this project we want to build and test a quantum node based on single-photon QD sources coupled to a 87Rb vapor cell. In particular it will be tested for the first time the possibility of using two distinct QDs for the implementation of a teleportation protocol, where the two single-photon sources will be frequency locked to the absolute frequency reference represented by the absorption line of the vapor cell.