Magnetic interactions are frustrated, if a spin cannot arrange its orientation such that it profits from the interaction with its neighbors. The logo shows the example of Ising spins ( which can only point up or down ) with antiferromagnetic interactions on a triangle. The third spin cannot gain energy, i.e., here spins with antiferro interactions are frustrated.
Frustration can prevent magnetic order; an outstanding example is the Kitaev model on the honeycomb lattice which forms a spin liquid ground state. Here our research focuses on questions as: What is the effect of Heisenberg-type perturbations in this model, or what are the consequences of magnetic fields and defects in the Kitaev-Heisenberg model?
Further research topics include: the Compass-Heisenberg model on the square lattice; moreover we are interested in spin chains formed by copper-oxygen units with frustrated interactions and helical magnetic order.
Another research topic are one-dimensional Wigner lattices and their magnetic interactions. Finally it should be stressed, that there is a close connection to the research on generalized spin-orbital models, which are generically frustrated.