AC-driven Quantum Phase Transitions

• Applicant: Privatdozent Dr. Gernot Schaller, since 4/2017
• Subject Area: Theoretical Condensed Matter Physics ; Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: from 2013 to 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 235452962

A quantum phase transition is a drastic change of state of a many-body system which occurs at zero temperature. Relatively little is known about such critical behaviour under nonequilibrium conditions, which in this project will be generated by periodic fields (`AC-driving'). Our key objectives are- to theoretically formulate, analyse, and interpret AC-driven quantum phase transitions. - to investigate the existence of novel states of matter under the effect of a nonadiabatic monochromatic driving with no analogues in static systems.- to apply established analytical and numerical methods in order to describe AC-driven critical behavior for so far unexplored models. - to explore the use of new theoretical methods, such as an effective partition function and the geometrical phase (Berry phase), in order to analyse critical phenomena under nonequilibrium conditions.- to discuss the relevance of the results for recent state-of-the-art experiments such as Bose-Einstein condensates in optical cavities.

• DFG Programme: Research Grants
• Ehemaliger Antragsteller: Professor Dr. Tobias Brandes, until 4/2017 (†)