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Updated: Jun 8, 2026

Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Photonic phase gate via an exchange of fermionic spin waves in a spin chain
Alexey V Gorshkov1, Johannes Otterbach, Eugene Demler
1Physics Department, Harvard University, Cambridge, Massachusetts 02138, USA.
Abstract:
We propose a new protocol for implementing the two-qubit photonic phase gate. In our approach, the π phase is acquired by mapping two single photons into atomic excitations with fermionic character and exchanging their positions. The fermionic excitations are realized as spin waves in a spin chain, while photon storage techniques provide the interface between the photons and the spin waves. Possible imperfections and experimental systems suitable for implementing the gate are discussed.
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