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Interactions and Interference in Quantum Dots: Kinks in Coulomb Blockade Peak Positions

H. U. Baranger·D. Ullmo·L. I. Glazman
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Abstract

We investigate the spin of the ground state of a geometrically confined many-electron system. For atoms, shell structure simplifies this problem-- the spin is prescribed by the well-known Hund's rule. In contrast, quantum dots provide a controllable setting for studying the interplay of quantum interference and electron-electron interactions in general cases. In a generic confining potential, the shell-structure argument suggests a singlet ground state for an even number of electrons. The interaction among the electrons produces, however, accidental occurrences of spin-triplet ground states, even for weak interaction, a limit which we analyze explicitly. Variaton of an external parameter causes sudden switching between these states and hence a kink in the conductance. Experimental study of these kinks would yield the exchange energy for the ``chaotic electron gas''.

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H. U. Baranger, D. Ullmo, L. I. Glazman. 1999-07-19. Interactions and Interference in Quantum Dots: Kinks in Coulomb Blockade Peak Positions. https://doi.org/10.1103/physrevb.61.r2425

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