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Title: Bell state analyzer for spectrally distinct photons

We demonstrate a Bell state analyzer that operates directly on frequency mismatch. Based on electro-optic modulators and Fourier-transform pulse shapers, our quantum frequency processor design implements interleaved Hadamard gates in discrete frequency modes. Experimental tests on entangled-photon inputs reveal fidelities of∼<#comment/>98%<#comment/>for discriminating between the|Ψ<#comment/>+⟩<#comment/>and|Ψ<#comment/>−<#comment/>⟩<#comment/>frequency-bin Bell states. Our approach resolves the tension between wavelength-multiplexed state transport and high-fidelity Bell state measurements, which typically require spectral indistinguishability.

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Optical Society of America
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Article No. 280
Medium: X
Sponsoring Org:
National Science Foundation
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