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We're looking for some support in the Regensburg carbon nanotube nanomechanics team! The job description can be found below; please e-mail me if interested! The position is available immediately, however I'm travelling during March and may be hard to reach, so arranging a meeting and a presentation may take a bit of time...

You have already been working successfully with millikelvin RF equipment in your PhD research, and have a good understanding of low temperature physics as well as gigahertz technology? Ideally, you are coming from a research group specialized in superconductor-related mesoscopic physics, quantum information, or cavity QED? You are interested in contributing to a young and dynamic team, trying to push the limits of what is doable in nano-electromechanical systems?
Then you might be just about right here. Your will conduct measurements on coupled superconductor-carbon nanotube nano-electromechanical systems, with a low-temperature high frequency measurement setup in a state-of-the-art dilution refrigerator. Our NEMS team consists at the moment of one PhD student and two MSc students (who you'll help supervise). We expect your work to lead to exceptional publications!
Your salary will be based on the German TV-L E13 (info in German). Regensburg university has a strong focus on nanophysics, in particular on spin phenomena and carbon-based systems. The natives are friendly, and while our university buildings feature classic 1965 concrete, the medieval city of Regensburgis a jewel on its own, with a vibrant young atmosphere. Both mountains and Munich airport are not far away.
Interested? Have a look at our web pages, and contact Andreas K. Hüttel (e-mail: andreas.huettel@physik.uni-r.de) for more information!

A lot of things have happened recently in our nanotube / nanomechanics research group in Regensburg... First of all, I'd like to congratulate Peter Stiller for finishing off his Diploma thesis and thereby his degree. Peter is immediately continuing as a PhD student, however switching topic from nanomechanics to charge qubits in carbon nanotubes - a newly founded project in the SFB 631. Here we plan to couple electronic quantum states in carbon nanotube double quantum dots to the electric field of a coplanar microwave resonator.
Then, straight from München and the research group of Jan von Delft, Alois Dirnaichner will join us soon as PhD student to work on experimental and theoretical characterization of few-electron states in ultraclean suspended carbon nanotubes. This is a project pursued together with the groups of Milena Grifoni and Christoph Strunk; we hope that the high quality of our carbon nanotubes enables us to do fundamental observations and analysis on unperturbed electronic multi-particle states.
Next, Sabine Kugler joins the nanomechanics team for her MSc thesis project. She will continue the development of chip geometries and materials suitable for combining carbon nanotubes with complex electronics, and help us with the characterization measurements.
Finally, last but not least, Hermann Kraus starts in december as a Diploma student, and will focus on high-frequency electronics at very low temperatures and superconducting nanocircuitry. Time to get these electrons rock'n'roll!

We're currently planning a research project in close collaboration with the theory group Prof. M. Grifoni, with working title "Transport spectroscopy and theoretical analysis of interacting few-carrier systems in semiconducting and small-bandgap carbon nanotubes". It combines equal parts of experimental work and theoretical data analysis and modelling. You've already done an excellent solid-state physics theory Diploma or MSc thesis and liked it, but would like to get your hands dirty as well? Then you're maybe the perfect candidate!

Interested? Please have a look at the PDF file with more details, at our web pages (group Prof. M. Grifoni, group Prof. C. Strunk, group Dr. A. K. Hüttel), and contact Andreas K. Hüttel (e-mail: andreas.huettel@physik.uni-r.de) for more information!

I'm very glad to be able to report that our manuscript "Universality of the Kondo effect in quantum dots with ferromagnetic leads", describing results that we've been working on during the last months, was just accepted for publication in  Physical Review Letters.
So what is it about, in a few simple words?
In general, much of our work is about charges trapped inside carbon nanotubes at very low temperatures (0.05K). Such a trap for e.g. electrons is called a quantum dot; similar to the electron shell of an atom or molecule, the laws of quantum mechanics force the electrons to occupy specific discrete levels, or quantum states. By looking at a tiny tunnel current through a quantum dot we can characterize its quantum mechanical properties; this is called transport spectroscopy.
The Kondo effect is a special case, as it is caused by strong interaction between localized charges inside the quantum dot and charges in the leads that we attach to the quantum dot. Whenever the localized charge can assume either of two (or more) states with equal energy ("degenerate states") and these states all couple to the leads, the Kondo effect causes an extra electrical conductance through the system. This is one of the simplest many particle effects in quantum mechanics and has fascinated researchers for quite some time; its behaviour is called universal, as it is independent of many detailed properties of the system at hand. In a non-magnetic system, the degenerate states are usually given by different directions of the electron internal magnetic moment, its spin.
Now, we contact our nanotube quantum dot with magnetic contacts. In these contacts, 1) the different directions of spin can couple differently to the quantum dot, and 2) the number of charges with one spin direction differs from the other (that's just what makes them magnetic). Among other things, we've been able to show that all this modification just acts on the Kondo effect the same way as an (imagined) magnetic field, so by applying the reverse magnetic field with an external magnet coil, we can restore the universal behaviour as known from non-magnetic systems. This makes the system much easier to describe, and will, we hope, be useful for future work in spintronics, where the magnetic moments are to be used for information processing.

"Universality of the Kondo effect in quantum dots with ferromagnetic leads"
M. Gaass, A. K. Hüttel, K. Kang, I. Weymann, J. von Delft, and Ch. Strunk
accepted for publication by Physical Review Letters; arXiv:1104.5699 (PDF)

Note: the Wikipedia articles "quantum dot" and "Kondo effect" are not wrong, but describe special uses of these terms and not the most general case as known today. Unfortunately this makes them completely useless as references here...