Keynote
Molecular Half Metallicity - a New Magnetic and Spin Transport Property at the Single Molecule Level

Half metals can generate 100% spin polarized currents since they behave as metals for one spin type and as insulators for the opposite spin. However, when the size of traditional half metals is reduced to the nanometer scale this property is not preserved, preventing its use for efficient spin manipulations at the nanoscale. Here, we show that a single magnetic molecule connected to non-magnetic electrodes can act as a half metal with more than 90% spin filtering. This unusual behaviour is explained in the framework of spin splitting of molecular energy levels. The observed molecular half metallicity paves the way for a variety of novel magnetic and spin transport effects.