Perturbation theories for open System Detector dynamics

• Applicant: Privatdozent Dr. Gernot Schaller
• Subject Area: Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: from 2010 to 2014
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 181060849

The conventional theory of quantum dissipation assumes the reservoir as being stationary, although the coupling between system and reservoir is usually mediated by exchange of e.g. energy or particles. However, this approach conflicts with the dynamical evolution of a detector as part of the reservoir that measures for example the particle (or energy) flux through the system. In addition, the dynamics of a fragile quantum system may be significantly altered by the mere presence of a quantum detector – even when no measurement is performed, such that a quantum-mechanical description of the detector dynamics is necessary. The present proposal suggests to expand theoretical methods that resolve this fundamental problem. For systems admitting transport, the proposal suggests the complete treatment of a system interacting with a quantum detector. Technically, the full density matrix in this approach is approximated by a (generalized) sum of time-dependent tensor products and thus goes beyond the Born approximation. The approach also enables the inclusion of detector back-action, which is of vital importance for a correct interpretation of experimental data.

• DFG Programme: Research Grants