Decoherence within a single atom

• Authors: Gyula Bene
• Languages of publication: EN

Abstracts

EN

An “almost diagonal” reduced density matrix (in coordinate representation) is usually a result of environment induced decherence and is considered the sign of classical behavior. We show that the proton of a ground state hydrogen atom can indeed possess such a density matrix. This example demonstrates that the “almost diagonal” structure may be derived from an interaction with a low number of degrees of freedom which play the role of the environment. We also show that decoherence effects in our example can only be observed if the interaction with the measuring device is significantly faster than the interaction with the environment (the electron). In the opposite case, when the interaction with the environment is significant during the measurement process, coherence is maintained. Finally, we propose a neutron scattering experiment on cold He atoms to observe decoherence which shows up as an additional positive contribution to the differential scattering cross section. This contribution is inversely proportional to the bombarding energy.

Keywords

EN

decoherence; atom optics; Franck-Condon effect; neutron scattering; 03.65.-w; 03.75.Be

• Publisher: De Gruyter Open
• Journal: Open Physics
• Year: 2003
• Volume: 1
• Issue: 2
• Pages: 332-343

Dates

published

1 - 6 - 2003

online

1 - 6 - 2003

Contributors

author

Gyula Bene

• Institute for Theoretical Physics, Eötvös University, Pázmány Péter sétány 1/A, H-1117, Budapest, Hungary

References

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Identifiers

DOI

10.2478/BF02476300