Observation of the Ettingshausen effect in quantum Hall systems

Evidence of the Ettingshausen effect in the breakdown regime of the integer quantum Hall effect has been observed in a GaAs/AlGaAs two-dimensional electron system. Resistance of micro Hall bars attached to both edges of a current channel shows remarkable asymmetric behaviors that indicate an electron temperature difference between the edges. The sign of the difference depends on the direction of the electric current and the polarity of the magnetic field. The results are consistent with the recent theory of Akera.