München 2004 – wissenschaftliches Programm

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A: Atomphysik

A 5: Neue Aspekte der Atomphysik I

A 5.1: Vortrag

Montag, 22. März 2004, 16:30–16:45, HS 132

Attosecond entanglement of protons and electrons in condensed matter - Compton scattering results and theoretical considerations — •C. Aris C.-Dreismann¹ and Tyno Abdul-Redah^1,2 — ¹Inst. f. Chemie, Stranski Lab., TU Berlin, D-10623 Berlin — ²ISIS Facility, R.A.L., Oxfordshire, OX11 0QX, U.K.

Several experiments on liquid and solid samples containing protons show a striking shortfall in the intensity of epithermal neutrons scattered by the protons [1-3]. E.g., neutrons colliding with water for just attoseconds (as) will see a ratio of H to O of roughly 1.5 to 1, instead of 2 to 1 [1,3]. Due to the large energy and momentum transfers applied in these neutron Compton scattering (NCS) experiments, the duration of a neutron-proton scattering event is about 50-500 as. Very recently [2,3] this effect has been confirmed using electron-proton Compton scattering (ECS) from a solid polymer [2,3]. Recall that electrons and neutrons interact with protons via fundamentally different forces – electromagnetic and strong. Theoretical considerations support the presence of attosecond quantum entanglement in the dynamics of the protons and the surrounding electrons. Note also that the time window of NCS and ECS is equal to the characteristic time of ’electron motion’, so that the widely used Born-Oppenheimer approximation is not applicable here.

[1] C. A. Chatzidimitriou-Dreismann et al., Phys. Rev. Lett. 79, 2839 (1997). [2] C. A. Chatzidimitriou-Dreismann et al. Phys. Rev. Lett. 91, 057403 (2003). [3] Cf.: Physics Today, sect. ’Physics Update’, p. 9, Sept. 2003; Scientific American, sect. ’News Scan’, p. 20, Oct. 2003