Recent experiments on engineered quantum systems made possible not only to monitor and study the time evolution of interacting quantum systems, but also to use them to perform quantum operations and quantum simulations. Experiments are typically carried out in a setting of trapped ultracold atoms, or using superconducting or magnetic artificial atoms as quantum bits. The role of dissipation in these systems is of utmost importance; it leads to dephasing and loss of information, destroys entanglement, but it also gives rise to heating and possibly thermalization. The goal of the thesis is to model such systems using matrix product operator (MPO) or, in a vectorized form, a matrix product state (MPS) approaches, and to study basic aspects of the time evolution in such systems, with a special focus on information spreading. The PhD student will not only carry out MPO and MPS calculations fur such systems, test quantum algorithms with them, but he/she will also compare these computations with the exact time evolution and also try and develop approximate methods such as non-Gaussian variational states, which may be useful to understand and benchmark larger quantum systems.
The Applicant must have good skills in analytical and numerical computations, a firm background in theoretical physics, and a geniune interest in numerical work.