Autonomous control of open non-equilibrium systems

• Applicant: Privatdozent Dr. Gernot Schaller
• Subject Area: Theoretical Condensed Matter Physics
• Term: from 2015 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 275705272

Quantum computers would allow for significantly faster algorithms for some extremely difficult problems. A further promise of well-controlled quantum systems are quantum teleportation and quantum cryptography. Whereas the latter application has become reality, the practical application of the first is still hampered by large problems: Quantum system can in the laboratory only be prepared, isolated and controlled with extreme efforts. Therefore, in the moment any effort is taken in the quest of alternative methods of controlling quantum systems, where the particular objectives may be quite different. Correspondingly, the control can also be realized differently: External control requires measurements to be performed on the quantum system, processing of the results and suitable control operations on the system, where the latter may be of unitary or dissipative type. In contrast, for an autonomous control the system controls itself, where it can often be divided into two parts. One of these parts effectively assumes the role of the detector and also performs the control operations on the other part. Consequently, autonomous control does not require a sophisticated external feedback loop, the control protocol, however, is hard-wired in every system. In this proposal, several projects are suggested that study external and autonomous control in non-equilibrium quantum systems. The proposal shall lead to an improved understanding of quantum systems and their interaction with their environment. On the other hand, the control of quantum systems enables interesting applications.

• DFG Programme: Research Grants