ISBN 9783843919425

978-3-8439-1942-5, Reihe Physik

Timo Fischer
Decoherence of the Orientation State

171 Seiten, Dissertation Universität Duisburg-Essen (2014), Softcover, B5

Zusammenfassung / Abstract

The present thesis considers the rotation dynamics of extended quantum objects, such as molecules, interacting with an environment; the quantum-to-classical transition is of particular interest. The first part extends the Cartesian Wigner-Weyl-Moyal phase space formalism of quantum mechanics, so that quantum mechanics on curved configuration spaces can be represented as a statistical theory on phase space. This includes in particular the quantum-mechanical description of the rigid rotor dynamics. The second part starts with the derivation of the master equation of orientational decoherence, which provides a generic description of the decoherence process of the quantum-mechanical orientation state. Then the formation and dynamics of the so-called pointer states of orientational decoherence is studied, which are distinguished by the interaction with the environment. It is shown, that these states are solitonic, exponentially localized wave packets which move on classical phase space trajectories for sufficiently strong system-environment interaction, and it is discussed how superpositions of such pointer states turn into mixed states.