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arXiv · 1001.3837

Visualizing quantum entanglement and the EPR paradox during the photodissociation of a diatomic molecule using two ultrashort laser pulses

Szczepan Chelkowski·André D. Bandrauk
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Abstract

We investigate theoretically the dissociative ionization of a H2+ molecule using two ultrashort laser (pump-probe) pulses. The pump pulse prepares a dissociating nuclear wave packet on an ungerade surface of H2+. Next, an UV (or XUV) probe pulse ionizes this dissociating state at large (R = 20 - 100 bohr) internuclear distance. We calculate the momenta distributions of protons and photoelectrons which show a (two-slit-like) interference structure. A general, simple interference formula is obtained which depends on the electron and protons momenta, as well as on the pump-probe delay on the pulses durations and polarizations. This interference can be interpreted as visualization of an electron state delocalized over the two-centres. This state is an entangled state of a hydrogen atom with a momentum p and a proton with an opposite momentum. -p dissociating on the ungerade surface of H2+. This pump-probe scheme can be used to reveal the nonlocality of the electron which intuitively should be localized on just one of the protons separated by the distance R much larger than the atomic Bohr orbit.

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Szczepan Chelkowski, André D. Bandrauk. 2010-01-21. Visualizing quantum entanglement and the EPR paradox during the photodissociation of a diatomic molecule using two ultrashort laser pulses. https://doi.org/10.1103/physreva.81.062101

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