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arXiv · 1708.05484

Effective tuning of electron charge and spin distribution in a dot-ring nanostructure at the ZnO interface

Tapash Chakraborty·Aram Manaselyan·Manuk Barseghyan
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Abstract

Electronic states and the Aharonov-Bohm effect in ZnO quantum dot-ring nanostructures containing few interacting electrons reveal several unique features. We have shown here that in contrast to the dot-rings made of conventional semiconductors, such as InAs or GaAs, the dot-rings in ZnO heterojunctions demonstrate several unique characteristics due to the unusual properties of quantum dots and rings in ZnO. In particular the energy spectra of the ZnO dot-ring and the Aharnov-Bohm oscillations are strongly dependant on the electron number in the dot or in the ring. Therefore even small changes of the confinement potential, sizes of the dot-ring or the magnetic field can drastically change the energy spectra and the behavior of Aharonov-Bohm oscillations in the system. Due to this interesting phenomena it is possible to effectively control with high accuracy the electron charge and spin distribution inside the dot-ring structure. This controlling can be achieved either by changing the magnetic field or the confinement potentials.

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Tapash Chakraborty, Aram Manaselyan, Manuk Barseghyan. 2017-08-18. Effective tuning of electron charge and spin distribution in a dot-ring nanostructure at the ZnO interface. https://doi.org/10.1016/j.physe.2018.01.013

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