Thermoelectric (TE) properties of a single nanowire (NW) are investigated in a microlab which allows the determination of the Seebeck coefficient S and the conductivity σ. A significiant influence of the magnetization of a 70 nm ferromagnetic Ni-NW on its power factor S²σ is observed. We detected a strong magneto thermopower effect (MTP) of about 10% and an anisotropic magneto resistance (AMR) as a function of an external magnetic field B in the order of 1%. At T = 295 K and B = 0 T we determined the absolute value of S = -(19 ± 2) µV/K. At zero field the figure of merit ZT ≈ 0.02 was calculated using the Wiedemann-Franz-law for the thermal conductivity. The thermopower S increases considerably as a function of B up to 10% at B = 0.5 T, and with a magneto thermopower of ∂S/∂B ≈ -(3.8 ± 0,5) µV/(K . T). The AMR and MTP are related by ∂s/∂r ≈ -11 ± 1 (∂s = ∂S/S).The TE efficiency increases in a transversal magnetic field (B =0.5T) due to an enhanced power factor by nearly 20%.

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