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Measuring Optical Tunneling Times using a Hong-Ou-Mandel Interferometer.



Sergey Polyakov, Alan L. Migdall, Paul D. Lett, David Papoular, Pierre Clade, Colin McCormick


We report a prediction for the delay measured in an optical tunneling experiment using Hong-Ou-Mandel (HOM) interference, taking into account the Goos-Hanchen shift generalized to frustrated total internal reflection situations. We precisely state assumptions under which the tunneling delay measured by an HOM interferometer can be calculated. We show that, under these assumptions, the measured delay is the group delay, and that it becomes apparently ‘superluminal' for sufficiently thick air gaps. We also show how an HOM signal with multiple minima can be obtained, and that the shape of such a signal is not appreciably affected by the presence of the optical tunneling zone, thus ruling out the explanation of the anomalously short tunneling delays in terms of a reshaping of the wavepacket as it goes through the tunneling zone. Finally, we compare the predicted tunneling delay to a relevant classical delay and conclude that our predictions involve no non-causal effect.
Optics Express


Fast Light, Hong-ou-Mandel, Interferometer, Total Internal Reflection, Tunneling


Polyakov, S. , Migdall, A. , Lett, P. , Papoular, D. , Clade, P. and McCormick, C. (2008), Measuring Optical Tunneling Times using a Hong-Ou-Mandel Interferometer., Optics Express, [online],, (Accessed April 13, 2024)
Created September 23, 2008, Updated April 20, 2021