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Abraham's Force on a Highly Dispersive Medium



Paul D. Lett, L Wang


We consider the radiation force on highly dispersive media. In doing so we reconsider an experiment proposed to measure the Abraham force term in the stress-energy tensor at optical frequencies by measuring the displacement of a transparent dielectric caused by a light pulse passing through it. We demonstrate that, using a cold atomic vapor with a large normal dispersion as the sample medium, such an experiment should now be feasible. We also show that this radiation force can be measured for a light pulse in a highly anomalously dispersive medium, where the group velocity exceeds c. This leads to the non-intuitive result that the sample recoil changes direction.
Laser Spectroscopy
Publisher Info
World Scientific Publishing Company, Hackensack, NJ


Abraham's force, anomalous dispersion, Bose-Einstein condensation, electromagnetic theory, laser cooling, slow light, spectroscopy


Lett, P. and Wang, L. (2004), Abraham's Force on a Highly Dispersive Medium, World Scientific Publishing Company, Hackensack, NJ, [online], (Accessed June 25, 2024)


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Created February 2, 2004, Updated November 10, 2018