A note on the phase of photons

Yong‐Fan Chen, Yuchen Liu, Zen-Hsiang Tsai +2 more

We describe a simple method of the beat-note interferometer that directly and dynamically measures the phase shift of light pulses induced by highly dispersive samples. Using the method, we show intuitively that the storage and retrieval of light pulses in a medium due to the effect of electromagnetically induced transparency is a coherent process and, quantitatively, that there is no observable phase shift caused by the process. This method is sensitive enough that it can be used to measure the phase of a light pulse with energy on the order of a dozen photons.

Felix A. E. Pirani

Toshihico Arimitsu, Masashi Ban

The solvable model of the microscopic phase modulation, which was proposed previously by the authors, is investigated by the two-pulse photon echo.

Pasquale Acquaro

Hsiang-Yu Lo, Po-Ching Su, Yu‐Wei Cheng +2 more

We report on an experimental demonstration of applying the beat-note interferometer to simultaneously measure the phase and amplitude variations of light pulses after propagating through an electromagnetically induced transparency medium at femtowatt-light levels. Furthermore, we observe that the measured phase noise approaches the shot-noise level arising from the fluctuations of detected photons.

I. K. Karpenko