Southwest Quantum Information and Technology

Memory assisted quantum cryptography networks

Presenting Author: Mehdi Namazi, Stony Brook University
Contributing Author(s): Mael Flament, Bertus Jordaan, Alessia Scriminich, Giuseppe Vallone, Reihaneh Shahrokhshahi, Paolo Villoresi, Eden Figueroa

The construction of an interconnected set of many quantum devices that performs long distance quantum communication is now within experimental reach. Therefore, it is of utmost relevance to engineer elementary networks of a few quantum nodes and quantum channels in order to understand and harness the potential of these novel architectures. We report the realization of a quantum communication network capable of performing memory-assisted measurement-device-independent quantum key distribution (MDI-QKD). We interconnect several quantum modules, each assigned to perform different tasks, achieving all capabilities needed for quantum cryptography. The components of our network are: (i) two independent random polarization qubit generators, (ii) two fiber based quantum communication channels, (iii) two portable quantum memories and (iv) a qubit decoder and reading station. Random qubits are sent over kilometers long links and coupled into a pair of dual-rail room temperature quantum memories. After storage and retrieval, the qubits are analyzed in a four-detector polarization setup. We achieve quantum bit error rates (QBER’s) of up to 3%, already fulfilling all the requirements needed to perform the BB84 and memory-assisted MDI-QKD protocols. This network will be the core of our four-memory entanglement distribution quantum repeater prototype.

Read this article online: https://arxiv.org/abs/1609.08676, https://journals.aps.org/prapplied/abstract/10.1103/PhysRevApplied.8.034023

(Session 5 : Thursday from 5:00pm - 7:00 pm)