Electrically driven nuclear spin resonance in single-molecule magnets

A recent publication in Science shows how coherent single nuclear-spin manipulation using electric fields only can be achieved. This quantum-mechanical process is present in all nuclear spin systems and uses of the hyperfine Stark effect as a magnetic field transducer at the atomic level. To read more see Science

First Time Electronic Read-out of Nuclear Spin States

For the first time nuclear spin states could be read out electronically by integrating single quantum magnets into circuits (in collaboration with W. Wernsdorfer). Long nuclear spin lifetimes (tens of seconds) and exceptional relaxation characteristics at the single-atom scale open the way to a completely new device world, into which quantum logics may be implemented. Nature

Real Space Observation of Spin-split Molecular Orbitals in Adsorbed SMMs

In collaboration with the group of R. Wiesendanger, the first direct real-space images of spin-split MOs at a TbPc2-Co(111) spinterface were reported in Nature Comms



Coupling Single Molecule Magnets to Ferromagnetic Substrates

The AF coupling of TbPc2 quantum magnets into a ferromagnetic substrate with observable remanescence up to 100 K was reported in an article in Phys Rev Lett


Supramolecular Spin Valves

The first demonstration of a fully functional spintronics device that is entirely made of molecular materials is reported in two publications Nature Materials and Nano Lett
More.... Press.

Surface-Confined Molecular Motors

The self-assembly of surface-confined molecular motors from simple molecular building blocks was reported in the Proceedings of the National Academy of Sciences (PNAS, in collaboration with J.V. Barth, TU München) More....

String Networks

An article in Nature Chemistry reports on the random reticulation of a metal surface by divergent coordination assembly expressing string formation and bifurcation motifs. More....

Giant Magnetic Anisotropy SMMs

The spin dynamics of a [TbPc2]-1-SMM was probed by solid-state 1H NMR techniques. The magnetic anisotropy barrier was found to be one order of magnitude larger than in any other SMM system (584 cm-1 - 641 cm-1). More ...

Dichotomous Array of Quantum Corrals


The confinement of surface-state electrons is possible using weak -interactions of aromatic molecules with metallic surfaces. The results obtained in collaboration with the group of J. V. Barth (TU Munich) demonstrate the engineering of ensembles of elaborate quantum resonance states by molecular self-assembly. More...

Expanding the Coordination Cage

A Ruthenium(II)-polypyridine complex exhibiting high quantum yields under ambient conditions was obtained by the expansion of the tpy coordination cage. More.....

Switching Nanostructures

Click to open larger picture The report on the nanostructuring of switchable iron (II) spin transition compounds by soft lithography techniques (in collaboration with
M. Cavallini, CNR Bologna) was highlighted as "Hot Paper" in the Angewandte Chemie. More... Press...

Transport through a Single Metal Ion


In collaboration with IBM, our group succeeded to study the electron transport through a single
Ru(tpy)2-molecule. It was shown that the transport occurs in the resonant tunnelling regime and the ruthenium(II) metal ion behaves like the cross shaft in a Cardan-joint. More...

Scientific Scope

The research activity of the Functional Molecular Nanostructures Group at the Institute of Nanotechnology in Karlsruhe is oriented towards the design of functional nanosystems by state-of-the-art organic/inorganic synthesis and supramolecular self-assembly techniques.


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The vision of the research group is to develop new concepts and advance research tools to master the design and the characterisation of molecular structures as well as their implementation and integration within the nanometer-regime. Towards this end, the group is highly integrated into several interdisciplinary collaborations and is directing several interdisciplinary European network projects




Breakthrough experiments have been carried out by the group targeting the self-assembly of spintronic devices. Supramolecular techniques were used to position magnetic molecules in defined device environments where single-spin addressing leads to the observation of magnetoresistive effects. The demonstrated possibility of manipulating spins at the single molecule limit opens a completely new world to Supramolecular Spintronic Devices, where memory, logic and possibly quantum logic may be integrated.




Molecules can be considered as physical Quantum Objects. The use of molecular materials represents the advantage that the active quantum processing elements consist of an atomic core of one-to-few open spin ions surrounded by a shell of organic material. At low temperature such molecular spin objects behave as simple, few-level systems and their spin degree of freedom can be sufficiently decoupled from the environment to achieve long decoherence times and making them to ideal candidates for the implementation of qubits. Since quantum coherence and stable entanglement of electron spins are extremely difficult to achieve, alternative concepts propose the use of nuclear spins (embedded in a controlled organic environment) as quantum information carrier. Nuclear spins are extremely well isolated from environment and less prone to decoherence, and the coherent manipulation can be adapted by tailoring the molecular environment. However, although being well isolated from their surroundings, nuclear spins have to be addressed, ideally electronically since complementary with existing technologies. The delicate balance between decoupling of the quantum object for stable coherence and connecting it for read out can be carried out by synthetic engineering of the molecular components. The first example of such successful realization of Molecular Quantum Spintronics, the completely electronic read out of a nuclear spin of a lanthanide ion (bearing electron and nuclear spins) embedded in a molecule (TbPc2), was recently reported in Nature





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