Shubnikov-de Haas (SdH) oscillations under a dc current bias are
experimentally studied on a Hall bar sample of single layer graphene. In dc
resistance, the bias current shows the common damping effect on the SdH
oscillations and the effect can be well accounted for by an elevated electron
temperature that is found to be linearly dependent on the current bias. In
differential resistance, a novel phase inversion of the SdH oscillations has
been observed with increasing dc bias, namely we observe the oscillation maxima
develop into minima and vice versa. Moreover, it is found that the onset
biasing current, at which a SdH extremum is about to invert, is linearly
dependent on the magnetic field of the SdH extrema. These observations are
quantitatively explained with the help of a general SdH formula.Comment: 5 pages, 4 figures, A few references adde