We have investigated the electrical Hanle effect with magnetic fields appliedat an oblique angle ({\theta}) to the spin direction (the oblique Hanle effect,OHE) in CoFe/MgO/semiconductor (SC) contacts by employing a three-terminalmeasurement scheme. The electrical oblique Hanle signals obtained inCoFe/MgO/Si and CoFe/MgO/Ge contacts show clearly different line shapesdepending on the spin lifetime of the host SC. Notably, at moderate magneticfields, the asymptotic values of the oblique Hanle signals (in both contacts)are consistently reduced by a factor of cos^2({\theta}) irrespective of thebias current and temperature. These results are in good agreement withpredictions of the spin precession and relaxation model for the electricaloblique Hanle effect. At high magnetic fields where the magnetization of CoFeis significantly tilted from the film plane to the magnetic field direction, wefind that the observed angular dependence of voltage signals in the CoFe/MgO/Siand CoFe/MgO/Ge contacts are well explained by the OHE, considering themisalignment angle between the external magnetic field and the magnetization ofCoFe.
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