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arXiv · 0810.0333

Effect of many-body quantum fluctuations on matrix Berry phases of a two-dimensional n-type semiconductor quantum dot

S. C. Kim·Y. J. Kim·P. S. Park·N. Y. Hwang·S. -R. Eric Yang
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Abstract

In the presence of spin-orbit coupling and inversion symmetry of the lateral confinement potential a single electron does not exhibit matrix Berry phases in quasi-two-dimensional semiconductor quantum dots. In such a system we investigate whether many-body correlation effects can lead to finite matrix Berry phases. We find that the transformation properties of many-electron wavefunctions under two-dimensional inversion operation do not allow finite matrix Berry phases. This effect is exact and is independent of the form of electron-electron interactions. On the other hand, quasi-two-dimensional semiconductor quantum dots with lateral confinement potential without inversion symmetry can have finite matrix Berry phases. We find that many-body quantum fluctuations can change matrix Berry phases significantly in such systems.

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S. C. Kim, Y. J. Kim, P. S. Park, N. Y. Hwang, S. -R. Eric Yang. 2008-10-02. Effect of many-body quantum fluctuations on matrix Berry phases of a two-dimensional n-type semiconductor quantum dot. https://doi.org/10.1088/0953-8984%2F20%2F42%2F425224

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