TY  - THES
AB  - Understanding how the macroscopically observable behavior of systems with many degrees of freedom emerges from the laws governing their microscopic constituents is an intriguing fundamental problem. We approach this issue by investigating how the dynamics of many-body quantum systems is affected by weak-to-moderate perturbations in three different nonequilibrium setups. First, we study the relaxation towards equilibrium under the influence of time-independent perturbations. Second, we consider so-called echo protocols, where the system relaxes for a certain time followed by an effective time reversal during another period of equal duration, spoiled by small inaccuracies in the state at the point of reversal or in the dynamical laws. Third, we analyze the response to external driving in the form of a time-dependent coupling strength for perturbations of a similar kind as in the first setup. These settings cover a large variety of different phenomena and applications such as the relaxation of system-bath compounds, prethermalization, magnetic resonance imaging, quantum quenches, and periodically modulated external fields. Adopting typicality arguments, we derive analytical predictions for the observable dynamics in all three scenarios. Furthermore, we analyze these predictions and verify them by comparison with numerical and experimental data for several different models and observables.
DA  - 2021
DO  - 10.4119/unibi/2951246
LA  - eng
PY  - 2021
TI  - Predicting quantum many-body dynamics out of equilibrium
UR  - https://nbn-resolving.org/urn:nbn:de:0070-pub-29512464
Y2  - 2024-11-22T10:34:19
ER  -