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Effects of geometry and impurities on quantum rings in magnetic fields

Research output: Contribution to journalArticleScientificpeer-review

Details

Original languageEnglish
Article number195310
Number of pages8
JournalPhysical Review B
Volume73
Issue number19
DOIs
Publication statusPublished - May 2006
Externally publishedYes
Publication typeA1 Journal article-refereed

Abstract

We investigate the effects of impurities and changing ring geometry on the energetics of quantum rings under different magnetic field strengths. We show that as the magnetic field and/or the electron number are/is increased, both the quasiperiodic Aharonov-Bohm oscillations and various magnetic phases become insensitive to whether the ring is circular or square in shape. This is in qualitative agreement with experiments. However, we also find that the Aharonov-Bohm oscillation can be greatly phase shifted by only a few impurities and can be completely obliterated by a high level of impurity density. In the many-electron calculations we use a recently developed fourth-order imaginary time projection algorithm that can exactly compute the density matrix of a free electron in a uniform magnetic field.

Keywords

  • MAXIMUM-DENSITY-DROPLET, BLOCKADE PEAK SPACINGS, DOTS, STATISTICS, EQUATIONS, ENERGY