We study the effect of mode coupling on the magnetoconductance fluctuations of a square ballistic quantum dot fabricated in AlGaAs/GaAs heterostructure material and defined by Schottky gates. Structures prepared allow for the independent variation of the number of propagating input and output modes and their coupling to the main cavity. While adjusting the opening of the input and output point contacts changes the number of modes allowed to propagate into the dot, the excitation from a quantum wire creates an additional selection rule. The autocorrelation and Fourier analyses of the fluctuations demonstrate that the formation of the quantum wire has a strong effect, not only on the average conductance of the dot but also on the excitation of the semiclassical orbits within it.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering
- Materials Chemistry