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arXiv · 2112.00658

Quantum Fourier transform on photonic qubits using cavity QED

Yu Shi·Edo Waks
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Abstract

We propose a quantum Fourier transform on photons in which a single atom-coupled cavity system mediates the photon-photon interactions. Our protocol utilizes time-delay feedback of photons and requires no active feedforward control. The time-delay feedback enables a single atom-cavity system to implement a quantum Fourier transform on an arbitrary number of photonic qubits on-the-fly, while rapid tuning of the atomic transition implements arbitrary controlled-phase gates. We analyze the performance of the protocol numerically and show that it can implement quantum Fourier transforms with tens of photons using state-of-the-art cavity quantum electrodynamics.

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Yu Shi, Edo Waks. 2021-12-01. Quantum Fourier transform on photonic qubits using cavity QED. https://doi.org/10.1103/physreva.106.013709

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