Quantum interference in nanometric devices: ballistic transport across arrays of T-shaped quantum wires

G. Goldoni; F. Rossi; E. Molinari

doi:10.1063/1.119954

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arXiv · cond-mat/9708020

Quantum interference in nanometric devices: ballistic transport across arrays of T-shaped quantum wires

G. Goldoni·F. Rossi·E. Molinari

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Abstract

We propose that the recently realized T-shaped semiconductor quantum wires (T-wires) could be exploited as three-terminal quantum interference devices. T-wires are formed by intersecting two quantum wells (QWs). By use of a scattering matrix approach and the Landauer-Büttiker theory, we calculate the conductance for ballistic transport in the parent QWs and across the wire region as a function of the injection energy. We show that different conductance profiles can be selected by tailoring the widths of the QWs and/or combining more wires on the scale of the Fermi wavelength. Finally, we discuss the possibility of obtaining spin-dependent conductance of ballistic holes in the same structures.

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G. Goldoni, F. Rossi, E. Molinari. 1997-08-04. Quantum interference in nanometric devices: ballistic transport across arrays of T-shaped quantum wires. https://doi.org/10.1063/1.119954

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