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arXiv · 2103.13095

A Quantum-Logic Gate between Distant Quantum-Network Modules

Severin Daiss·Stefan Langenfeld·Stephan Welte·Emanuele Distante·Philip Thomas·Lukas Hartung·Olivier Morin·Gerhard Rempe
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Abstract

The big challenge in quantum computing is to realize scalable multi-qubit systems with cross-talk free addressability and efficient coupling of arbitrarily selected qubits. Quantum networks promise a solution by integrating smaller qubit modules to a larger computing cluster. Such a distributed architecture, however, requires the capability to execute quantum-logic gates between distant qubits. Here we experimentally realize such a gate over a distance of 60m. We employ an ancillary photon that we successively reflect from two remote qubit modules, followed by a heralding photon detection which triggers a final qubit rotation. We use the gate for remote entanglement creation of all four Bell states. Our non-local quantum-logic gate could be extended both to multiple qubits and many modules for a tailor-made multi-qubit computing register.

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Severin Daiss, Stefan Langenfeld, Stephan Welte, Emanuele Distante, Philip Thomas, Lukas Hartung, Olivier Morin, Gerhard Rempe. 2021-03-24. A Quantum-Logic Gate between Distant Quantum-Network Modules. https://doi.org/10.1126/science.abe3150

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