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DY: Fachverband Dynamik und Statistische Physik
DY 6: Quantum Dynamics, Decoherence, and Quantum Information I
DY 6.1: Talk
Monday, March 14, 2011, 14:00–14:15, ZEU 255
Attosecond dynamics and decoherence in neutron-H2 scattering — •C. Aris Dreismann1, Evan Gray2, and Tom Blach2 — 1Institute of Chemistry, TU Berlin, Germany — 2Griffith University, School of Biomolecular and Physical Sciences, Brisbane, Australia
The standard theory of neutron scattering is based on time-dependent first order perturbation theory (Fermi’s Golden Rule); see e.g. [1]. However, the characteristic time-window of neutron Compton scattering (NCS) in the energy transfer range of 1-100 eV lies in the attosecond range, in which the applicability of the Golden Rule becomes questionable. It is argued that, in the NCS physical context, quantum entanglement and decoherence play a significant role [2]. Results of current NCS experiments from H2 and D2 in the gas phase at T = 41 K are reported, showing that the measured Compton profiles reveal new features of quantum dynamics which contradict conventional theoretical expectations. The non-unitary dynamical character of this ultrafast scattering experiments is discussed, and the specific role of decoherence is pointed out. The presented results indicate that the new effect under investigation may play a significant role also in other scattering experimental fiels.
[1] G. L. Squires, Thermal Neutron Scattering, Dover (1996). [2] C. A. Chatzidimitriou-Dreismann and M. Krzystyniak, Laser Physics 20, 990 (2010).