  Over the last two decades organic spintronics has developed into a striving
field with exciting reports of long spin diffusion lengths and spin relaxation
times in organic semiconductors (OSCs). Easily processed and inexpensive, OSCs
are considered a potential alternative to inorganic materials for use in
spintronic applications. Spin currents have been detected in a wide range of
materials, however, there is still uncertainty over the origin of the signals.
Recently, we explored spin transport through an organic semiconductor with
lateral spin injection and detection architectures, where the injected spin
current is detected non-locally via spin-to-charge conversion in an inorganic
detector. In this work we show that the widely-used control experiments like
linear power dependence and inversion of the signal with the magnetic field are
not sufficient evidence of spin transport and can lead to an incorrect
interpretation of the signal. Here, we use in-plane angular dependent
measurements to separate pure spin signal from parasitic effects arising from
spin rectification (SREs). Apart from well established anisotropic
magnetoresistance (AMR) and anomalous Hall effect (AHE), we observed a novel
effect which we call spurious inverse spin Hall effect (ISHE). It strongly
resembles ISHE behaviour, but arises in the ferromagnet rather than the
detector meaning this additional effect has to be considered in future work.
