Diploma thesis

In 2005 I completed my Diploma thesis in the quantum information group at the University of Potsdam. Questions on linear optics including how to exploit different degrees of freedom were of central interest.


Between October 2005 and October 2008 I was a PhD student in the Quantum Information Theory group at the Institute for Mathematical Sciences, Imperial College London, sponsored by Microsoft Research through the European PhD Scholarship. The Physics behind the effects I was interested in are described by Quantum Optics. More precisely, my PhD project is concerned with the capabilities of linear optics as possible hardware to realize quantum information processing devices.

That means on the one hand to find methods to describe and solve the problem of how to implement given unitaries on dual-rail encoding with beam splitters. Particularly interesting is, of course, to find the optimal solutions to these problem, i.e., the solutions that work with the highest probability of success within the set of rules defined in the beginning.

A more relaxed version of this task is concerned with the generation of special quantum states. Given a certain input (e.g., single photons), how to produce a given state.

On the other hand, given certain quantum gates that are implemented in linear optics (and therefore only work probabilistically), how to apply them to given resources (e.g., EPR pairs) to generate other states, such that the resource requirement is the least possible. Actually, this task is an entirely classical problem.

Further, questions for fundamental limits inherent in linear optics were addressed.

The final version of my PhD thesis can be found here, a PDF suitable for eBook-readers is available here.

Research Interest

At the moment I am a postdoctoral researcher at the University of Potsdam.

Besides various questions in linear optics I am investigating optomechanical systems. These are, for example, tiny mirrors which are probed with classical or quantum states of light. Signatures of quantum behaviour of this mesoscopic mechanical system and effects of the environment can be identified.

A BibTeX file of my publications can be found here.