QUANTUM OSCILLATIONS OF TRANSVERSE RESISTANCE IN SERIES AND SINGLE POINT-CONTACT CONFIGURATIONS

We report in this work quantum oscillations in transverse resistance in series and single point-contact (PC) configurations. In the series case, both under zero and finite magnetic fields, an oscillation corresponding to the plateaus of the longitudinal resistance was observed. In the single PC with an accurate structure symmetry, a similar oscillation appeared only when a finite magnetic field was applied. In addition, it is confirmed that the oscillations occur at equilibrium conditions and their polarity is odd against reversal of the current direction. These results indicate a new and equilibrium origin of the oscillation, which is different from the oscillatory thermopower.