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Discontinuities in the level density of small quantum dots under strong magnetic fields

Augusto Gonzalez·Roberto Capote
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Abstract

Exact diagonalization studies of the level density in a six-electron quantum dot under magnetic fields around 7 T (``filling factor'' around 1/2) are reported. In any spin-polarization channel, two regimes are visible in the dot excitation spectrum: one corresponding to interacting quasiparticles (i.e. composite fermions) for excitation energies below 0.4 meV, and a second one for energies above 0.4 meV, in which the level density (exponentially) increases at the same rate as in the non-interacting composite-fermion model.

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Augusto Gonzalez, Roberto Capote. 2002-07-22. Discontinuities in the level density of small quantum dots under strong magnetic fields. https://doi.org/10.1103/physrevb.66.113311

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