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arXiv · 0911.4765

Correlated two-photon emission by transitions of Dirac-Volkov states in intense laser fields: QED predictions

E. Lötstedt·U. D. Jentschura
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Abstract

In an intense laser field, an electron may decay by emitting a pair of photons. The two photons emitted during the process, which can be interpreted as a laser-dressed double Compton scattering, remain entangled in a quantifiable way: namely, the so-called concurrence of the photon polarizations gives a gauge-invariant measure of the correlation of the hard gamma rays. We calculate the differential rate and concurrence for a backscattering setup of the electron and photon beam, employing Volkov states and propagators for the electron lines, thus accounting nonperturbatively for the electron-laser interaction. The nonperturbative results are shown to differ significantly compared to those obtained from the usual double Compton scattering.

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E. Lötstedt, U. D. Jentschura. 2009-11-25. Correlated two-photon emission by transitions of Dirac-Volkov states in intense laser fields: QED predictions. https://doi.org/10.1103/physreva.80.053419

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