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arXiv · 1611.02415

Time-resolved spectroscopy with entangled photons

Dmitry A. Kalashnikov·Elizaveta V. Melik-Gaykazyan·Alexey A. Kalachev·Ye Feng Yu·Arseniy I. Kuznetsov·Leonid A. Krivitsky
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Abstract

Interaction of light with media often occurs with a femtosecond response time. Its measurement by conventional techniques requires the use of femtosecond lasers and sophisticated time-gated optical detection1-3. Here we demonstrate that by exploiting quantum interference of entangled photons it is possible to measure the phase relaxation time of a media on the femtosecond time scale (down to 100 fs) using accessible continuous wave laser and single-photon counting. We insert the sample in the Hong-Ou-Mandel interferometer4 and infer the phase relaxation time from the modification of the two-photon interference pattern. In addition to its simplicity and ease of use, the technique does not require compensation of group velocity dispersion5-8 and does not induce photo-damage of the samples. This technique will be useful for characterization of ultrafast phase relaxation processes in material science, chemistry, and biology.

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BibTeXRIS

Dmitry A. Kalashnikov, Elizaveta V. Melik-Gaykazyan, Alexey A. Kalachev, Ye Feng Yu, Arseniy I. Kuznetsov, Leonid A. Krivitsky. 2016-11-08. Time-resolved spectroscopy with entangled photons. https://doi.org/10.1038/s41598-017-11694-z

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