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Periodic magnetoconductance fluctuations in triangular quantum dots in the absence of selective probing

Peter Boggild·Anders Kristensen·Henrik Bruus·Stephanie M. Reimann·Poul Erik Lindelof
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Abstract

We have studied the magnetoconductance of quantum dots with triangular symmetry and areas down to 0.2 square microns, made in a high mobility two-dimensional electron gas embedded in a GaAs-AlGaAs heterostructure. Semiclassical simulations show that the gross features in the measured magnetoconductance are caused by ballistic effects. Below 1 K we observe a strong periodic oscillation, which may be explained in terms of the Aharanov-Bohm flux quantization through the area of a single classical periodic orbit. From a numerical and analytical analysis of possible trajectories in hard- and soft-walled potentials, we identify this periodic orbit as the enscribed triangle. Contrary to other recent experiments, this orbit is not accessible by classical processes for the incoming collimated beam.

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Peter Boggild, Anders Kristensen, Henrik Bruus, Stephanie M. Reimann, Poul Erik Lindelof. 1998-07-14. Periodic magnetoconductance fluctuations in triangular quantum dots in the absence of selective probing. https://doi.org/10.1103/physrevb.57.15408

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