Research - Current Topics

Atomic spins are prepared by doping or by adsorbing magnetic atoms onto the surfaces of various solid state bodies. Their magnetic properties, i.e. magnetic moment, anisotropy, and dynamics of spin excitations, can be tailored by a proper choice of atomic species, coordination and solid state material.

Using the methodology of atom manipulation we can assemble, one atomic spin at a time, magnetic nanostructures on metallic surfaces of almost any conceivable shapes and magnetic couplings. Changing the separations of the atomic spins within the nanostructure...

Magnetism in low-dimensions is a fascinating topic: Even in apparently simple systems such as monolayers the nearest neighbor distance, the symmetry and the hybridization with the substrate can play a crucial role for the magnetic properties.

In a system exhibiting magnetic anisotropy, the magnetization direction of a single-domain particle shows preferential orientations in space, given by the minima of the anisotropy energy. For switching the magnetization direction between different easy axis states, the total anisotropy energy barrier has to be surmounted.

In this project magnetic properties of magnetic molecules are investigated. Different sample substrate systems with different electronic and magnetic properties are chosen to reveal the coupling of the molecules to each other and to the substrate...

Graphene is a monolayer of carbon atoms, which are arranged in a honeycomb lattice consisting of two equivalent triangular sublattices A and B. Graphene is a truly two-dimensional crystal and is the basic component of the other carbon allotropes with a sp² hybridization...

3D topological insulators are a new phase of quantum matter with a strong spin-orbit coupling. They exhibit insulating behaviour in the bulk while surface states lead to metallic conduction at the surfaces only. The surface states offer an unusual spin-polarized band structure not seen before.

Using the short-ranged electron-mediated magnetic exchange interaction to map spin-structures with atomic resolution was predicted as early as 1990. However, the breakthrough experiment on the antiferromagnetic insulator NiO(001) was not successfully performed until 2006 and published in Nature in 2007...

The scope of this study is to study the (in-)direct coupling between a nanoscale mechanical resonator and the ensemble of atoms in a Bose-Einstein condensate (BEC). The initial goal is trying to achieve the 'long-distance' ex situ coupling between a kHz mechanical oscillator and a one dimensional (1D) optical lattice.