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Topological Hunds rules and the electronic properties of a triple lateral quantum dot molecule

Marek Korkusinski·Irene Puerto Gimenez·Pawel Hawrylak·Louis Gaudreau·Sergei A. Studenikin·Andrew S. Sachrajda
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Abstract

We analyze theoretically and experimentally the electronic structure and charging diagram of three coupled lateral quantum dots filled with electrons. Using the Hubbard model and real-space exact diagonalization techniques we show that the electronic properties of this artificial molecule can be understood using a set of topological Hunds rules. These rules relate the multi-electron energy levels to spin and the inter-dot tunneling $t$, and control charging energies. We map out the charging diagram for up to N=6 electrons and predict a spin-polarized phase for two holes. The theoretical charging diagram is compared with the measured charging diagram of the gated triple-dot device.

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Marek Korkusinski, Irene Puerto Gimenez, Pawel Hawrylak, Louis Gaudreau, Sergei A. Studenikin, Andrew S. Sachrajda. 2007-02-26. Topological Hunds rules and the electronic properties of a triple lateral quantum dot molecule. https://doi.org/10.1103/physrevb.75.115301

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