Proximity-Induced Electronic and Magnetic Effects in Phthalocyanine/Graphene/h-BN Heterostructures

Graphene is an ideal building block of complex heterostructures. Normally, in proximity to molecular thin films its mobility is compromised. However, our recent results show that graphene in proximity to a molecular thin film of Copper Phthalocyanine (CuPc) preserves its mobility while transferring an important amount of electrons to CuPc (~10^12/cm^2). Additionally, we have found that weak localization in bilayer graphene is restored by the presence of the CuPc molecules.

Our heterostructures are fabricated by transferring graphene on hexagonal boron nitride (h-BN) and depositing through thermal evaporation of a phthalocyanine thin film. We plan to perform experiments using Manganese Phthalocyanine (MnPc), a similar molecule which has a higher magnetic moment than CuPc and an unpaired electron of S=3/2. MnPc is one of the few Pcs to develop long range magnetic order at low temperatures. We expect to see in electronic transport experiments on a MnPc / graphene / h-BN heterostructure signature of the proximity effects with a ferromagnetic molecular thin film, measured in the quantum coherence regime.