Tuning magnetic frustration of nanomagnets in triangular-lattice   geometry
  We study the configuration of magnetic moments on triangular lattices of single-domain ferromagnetic islands, examining the consequences of magnetostatic interactions in this frustrated geometry. By varying the island-island distance along one direction, we are able to tune the ratio of different interactions between neighboring islands, resulting in a corresponding variation in the local correlations between the island moments. Unlike other artificial frustrated magnets, this lattice geometry displays regions of ordered moment orientation, possibly resulting from a higher degree of anisotropy leading to a reduced level of frustration. 
Xianglin Ke, Jie Li, Sheng Zhang, Cristiano Nisoli, Vincent H. Crespi,   and Peter Schiffer