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Quantum dots based on parabolic quantum wells: importance of electronic correlations

T. Ihn·C. Ellenberger·C. Yannouleas·U. Landman·K. Ensslin·D. Driscoll·A. C. Gossard
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Abstract

We present measurements and theoretical interpretation of the magnetic field dependent excitation spectra of a two-electron quantum dot. The quantum dot is based on an Al$_x$Ga$_{1-x}$As parabolic quantum well with effective $g^\star$-factor close to zero. Results of tunneling spectroscopy of the four lowest states are compared to exact diagonalization calculations and a generalized Heitler--London approximation and good agreement is found. Electronic correlations, associated with the formation of an H$_2$-type Wigner molecule, turn out to be very important in this system.

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T. Ihn, C. Ellenberger, C. Yannouleas, U. Landman, K. Ensslin, D. Driscoll, A. C. Gossard. 2006-10-06. Quantum dots based on parabolic quantum wells: importance of electronic correlations. https://doi.org/10.1142/s0217979207042781

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