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تسجيل مستخدم جديدDesign of a Quantum-Repeater using Quantum-Circuits and benchmarking its performance on an IBM Quantum-Computer
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Quantum communication relies on the existence of entanglement between two nodes of a network. Since, entanglement can only be produced using local quantum operations, distribution of parts of this entangled system between different nodes becomes necessary. However, due to the extremely fragile nature of entanglement and the presence of losses in the communication channel, the direct distribution of entanglement over large distances is nearly impossible. Quantum repeaters have been proposed to solve this problem. These enable one to establish long-range entanglement by dividing the link into smaller parts, creating entanglement between each part and connecting them up to form the full link. As researchers race to establish entanglement over larger and larger distances, it becomes essential to gauge the performance and robustness of the different protocols that go into designing a quantum repeater, before deploying them in real life. Present day noisy quantum computers are ideal for this task as they can emulate the noisy environment in a quantum communication channel and provide a benchmark for how the protocols will perform on real-life hardware. In this paper, we report the circuit-level implementation of the complete architecture of a Quantum Repeater. All the protocols of the repeater have been bench-marked on IBM Q, the worlds first publicly available cloud quantum computer. The results of our experiment provide a measure for the fidelity of entanglement current repeaters can establish. In addition, the repeater protocol provides a robust benchmark for the current state-of-the-art of quantum computing hardware.
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