Spin‐dependent processes in ZnPc single layer devices

Applying continuous wave electrically detected magnetic resonance (EDMR) we investigate spin dependent currents in phthalocyanine thin films. Changing the electrode materials and geometries by switching from ITO/ZnPc/Al to coplanar Au/ZnPc/Au devices, we observe a change in sign and intensity of the signal. The shape and the resonance position of the signal do not change and are a fingerprint of the phthalocyanine material. We discuss two different models explaining our results and specifically the possibility of exchange coupling between the spins.