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Electronic structure of rectangular quantum dots

E. Räsänen·H. Saarikoski·V. N. Stavrou·A. Harju·M. J. Puska·R. M. Nieminen
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Abstract

We study the ground state properties of rectangular quantum dots by using the spin-density-functional theory and quantum Monte Carlo methods. The dot geometry is determined by an infinite hard-wall potential to enable comparison to manufactured, rectangular-shaped quantum dots. We show that the electronic structure is very sensitive to the deformation, and at realistic sizes the non-interacting picture determines the general behavior. However, close to the degenerate points where Hund's rule applies, we find spin-density-wave-like solutions bracketing the partially polarized states. In the quasi-one-dimensional limit we find permanent charge-density waves, and at a sufficiently large deformation or low density, there are strongly localized stable states with a broken spin-symmetry.

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E. Räsänen, H. Saarikoski, V. N. Stavrou, A. Harju, M. J. Puska, R. M. Nieminen. 2003-02-20. Electronic structure of rectangular quantum dots. https://doi.org/10.1103/physrevb.67.235307

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