Symmetry of Two-Terminal Nonlinear Electric Conduction

Department of Physics, University of Oregon, Eugene, Oregon, United States
Physical Review Letters (Impact Factor: 7.51). 02/2004; 92(4):046803. DOI: 10.1103/PhysRevLett.92.046803
Source: PubMed


The symmetry relations for the electric conductance of mesoscopic devices in the nonlinear regime and in the presence of magnetic field were discussed. The symmetry for the nonlinear conductance of two-dimensional electric conductors was considered under reversal of voltage, magnetic field, and lead orientation. The conductors without significant disorder were also considered. The deviations from perfect symmetry were measured using semiconductor quantum dots. The symmetry of nonlinear transport required geometrical symmetry of the conductor.

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