Tuning the magneto-optical response of TbPc2 single molecule magnets by the choice of the substrate

Abstract

In this work, we investigated the magneto-optical response of thin films of TbPc₂ on substrates which are relevant for (spin) organic field effect transistors (SiO₂) or vertical spin valves (Co) in order to explore the possibility of implementing TbPc₂ in magneto-electronic devices, the functionality of which includes optical reading. The optical and magneto-optical properties of TbPc₂ thin films prepared by organic molecular beam deposition (OMBD) on silicon substrates covered with native oxide were investigated by variable angle spectroscopic ellipsometry (VASE) and magneto-optical Kerr effect (MOKE) spectroscopy at room temperature. The magneto-optical activity of the TbPc₂ films can be significantly enhanced by one to two orders of magnitude upon changing the molecular orientation (from nearly standing molecules on SiO₂/Si substrates to nearly lying molecules on perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA) templated SiO₂/Si substrates) or by using metallic ferromagnetic substrates (Co).