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Spectroscopy by frequency entangled photon pairs

Atsushi Yabushita·Takayoshi Kobayashi
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Abstract

Quantum spectroscopy was performed using the frequency-entangled broadband photon pairs generated by spontaneous parametric down-conversion. An absorptive sample was placed in front of the idler photon detector, and the frequency of signal photons was resolved by a diffraction grating. The absorption spectrum of the sample was measured by counting the coincidences, and the result is in agreement with the one measured by a conventional spectrophotometer with a classical light source.

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Atsushi Yabushita, Takayoshi Kobayashi. 2004-01-05. Spectroscopy by frequency entangled photon pairs. https://doi.org/10.1103/physreva.69.013806

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