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arXiv · 1709.05274

Characterization of coherent quantum frequency combs using electro-optic phase modulation

Poolad Imany·Ogaga D. Odele·Jose A. Jaramillo-Villegas·Daniel E. Leaird·Andrew M. Weiner
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Abstract

We demonstrate a two-photon interference experiment for phase coherent biphoton frequency combs (BFCs), created through spectral amplitude filtering of biphotons with a continuous broadband spectrum. By using an electro-optic phase modulator, we project the BFC lines into sidebands that overlap in frequency. The resulting high-visibility interference patterns provide an approach to verify frequency-bin entanglement even with slow single-photon detectors; we show interference patterns with visibilities that surpass the classical threshold for qubit and qutrit states. Additionally, we show that with entangled qutrits, two-photon interference occurs even with projections onto different final frequency states. Finally, we show the versatility of this scheme for weak-light measurements by performing a series of two-dimensional experiments at different signal-idler frequency offsets to measure the dispersion of a single-mode fiber.

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Poolad Imany, Ogaga D. Odele, Jose A. Jaramillo-Villegas, Daniel E. Leaird, Andrew M. Weiner. 2017-09-15. Characterization of coherent quantum frequency combs using electro-optic phase modulation. https://doi.org/10.1103/physreva.97.013813

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