Far-reaching control

Markus Karl, Boris Nowak, Thomas Gasenzer

Possible universal dynamics of a many-body system far from thermal equilibrium are explored. A focus is set on meta-stable non-thermal states exhibiting critical properties such as self-similarity and independence of the details of how the respective state has been reached. It is proposed that universal dynamics far from equilibrium can be tuned to exhibit a dynamical transition where these critical properties change qualitatively. This is demonstrated for the case of a superfluid two-component Bose gas exhibiting different types of long-lived but non-thermal critical order. Scaling exponents controlled by the ratio of experimentally tuneable coupling parameters offer themselves as natural smoking guns. The results shed light on the wealth of universal phenomena expected to exist in the far-from-equilibrium realm.

Alexei S. Trifonov

Pau Martí Sanahuja

Nowadays, interest is shown in the development of quantum computers because in the future it is expected to reach their potential computational power, which is superior to legacy computers. Since the day where quantum computers phase the current technology into obsolescence is still far out of reach, a period of coexistence between the two technologies is expected as these new devices are improved. One of the possible uses for quantum computers is in datacenters, offering services as cloud. Anticipating to their introduction in datacenters, this Bachelor’s Thesis goal has been to develop a system that orchestrates and manages petitions for a datacenter with hybrid resources, with the objective of making optimal use of the two available technologies.

Noriaki Horiuchi

Paolo Facchi A, Giancarlo Garnero, Giuseppe Marmo +2 more

Dmitry V. Zhdanov

Why does controlling quantum phenomena appear easy to achieve? Why do effective quantum controls appear easy to find? Why is chemical synthesis and property optimization easier than expected? How to explain the commonalities across the optimal control applications in quantum mechanics, chemistry, material science, biological evolution and engineering? The theory of quantum control landscapes (QCL) is developed by Prof. Rabitz and his colleagues to address these puzzling questions. Unfortunately, the obtained conclusions are subject of gross misinterpretations which are spread in hundreds of published papers. We investigate, summarize and report several previously unknown subtleties of the QCL theory which have far-reaching implications for nearly all practical applications.