Quantum Information and Entanglement Theory

Controlled quantum dynamics is concerned with the preparation, control, read-out, and verification of composite quantum systems. This raises considerable experimental challenges but also leads us, quite naturally, to questions concerning the mathematical structure of states, dynamics and correlations in composite quantum systems. What are for example the most suitable mathematical structures for the description of the states and evolution of composite quantum systems or quantum many-body systems? Can we make use of this knowledge to efficiently learn the state of a many-body system?

Diamond Sensors and Simulators

A perfect diamond is transparent. What gives it colour are atomic sized defects in the lattices structure, aptly called colour centers which possess electronic and nuclear spin degrees of freedom that can be controlled and brought to interact by microwave and radiofrequency fields and whose states can be read out optically. Thanks to their remarkably long electron and nuclear spin coherence times colour centers are excellent candidates for the realization of quantum information processing, quantum simulation and quantum sensing.

Open Quantum Systems and Control

An open quantum system is a part of a larger, unmeasurable system whose reduced dynamics appears non-unitary.  We study how and when such composite systems can be described by master equations,  the  general validity of the Markovian approach and quantitative measures of deviations from Markovianity.  We also develop powerful many-body simulation methods to study realistic and non-perturbative problems in a variety of experimental systems.

Quantum Effects in Biology

In the last few years the study of Quantum Effects in Biology has emerged as a vibrant and cross-disciplinary field of research, in which both experiment and theory are providing mounting evidence that the high efficiency of many key biological processes may be partly derived from an exploitation of non-classical processes by nature. We investigate a variety of these phenomena, ranging from photosynthesis, magnetic sensing in birds and olfaction.

Quantum Many Body Systems and Control

We study dynamical and equilibrium properties of quantum many body systems from the quantum information science perspective. Main foci lie on the entanglement content of typical states and on the development of novel numerical tools to simulate and analyze these systems, in particular for time evolution.

Quantum Simulations with Trapped Particles

A universal quantum simulator is a quantum computer proposed by Richard Feynman in 1982. Feynman showed that a classical Turing machine would presumably experience an exponential slowdown when simulating quantum phenomena, while his hypothetical universal quantum simulator would not. David Deutsch in 1985, took the ideas further and described a Universal quantum computer. In 1996, Seth Lloydshowed that a standard quantum computer can be programmed to simulate any local quantum system efficiently.