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arXiv · 0908.2092

Wigner molecules in carbon-nanotube quantum dots

Andrea Secchi·Massimo Rontani
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Abstract

We demonstrate that electrons in quantum dots defined by electrostatic gates in semiconductor nanotubes freeze orderly in space realizing a `Wigner molecule'. Our exact diagonalisation calculations uncover the features of the electron molecule, which may be accessed by tunneling spectroscopy -indeed some of them have already been observed by Deshpande and Bockrath [Nature Phys. 4, 314 (2008)]. We show that numerical results are satisfactorily reproduced by a simple ansatz vibrational wave function: electrons have localized wave functions, like nuclei in an ordinary molecule, whereas low-energy excitations are collective vibrations of electrons around their equilibrium positions.

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Andrea Secchi, Massimo Rontani. 2009-08-14. Wigner molecules in carbon-nanotube quantum dots. https://doi.org/10.1103/physrevb.82.035417

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