Article

Quantum effects in linear and nonlinear transport of T-shaped ballistic junction patterned from GaAs/Al_ {x} Ga_ {1− x} As heterostructures

Physical review. B, Condensed matter (Impact Factor: 3.77). 06/2010; 81(23). DOI: 10.1103/PhysRevB.81.233306
Source: arXiv

ABSTRACT We report low-temperature transport measurements of three-terminal T-shaped device patterned from GaAs/AlxGa1−xAs heterostructure. We demonstrate the mode branching and bend resistance effects predicted by numerical modeling for linear conductance data. We show also that the backscattering at the junction area depends on the wave function parity. We find evidence that in a nonlinear transport regime the voltage of floating electrode always increases as a function of push-pull polarization. Such anomalous effect occurs for the symmetric device, provided the applied voltage is less than the Fermi energy in equilibrium.

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