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Dynamical and point symmetry of the Kondo effect in triangular quantum dot

Tetyana Kuzmenko·Konstantin Kikoin·Yshai Avishai
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Abstract

In this work we concentrate on the {\it point symmetry} of triangular triple quantum dot and its interplay with the {\it spin rotation symmetry} in the context of Kondo tunneling through this kind of artificial molecule. A fully symmetric triangular triple quantum dot is considered, consisting of three identical puddles with the same individual properties (energy levels and Coulomb blockade parameters) and inter-dot coupling (tunnel amplitudes and electrostatic interaction). The underlying Kondo physics is determined by the product of a discrete rotation symmetry group in real space and a continuous rotation symmetry in spin space. These symmetries are reflected in the resulting exchange hamiltonian which naturally involves spin and orbital degrees of freedom. The ensuing poor-man scaling equations are solved and the Kondo temperature is calculated.

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Tetyana Kuzmenko, Konstantin Kikoin, Yshai Avishai. 2004-12-20. Dynamical and point symmetry of the Kondo effect in triangular quantum dot. https://doi.org/10.1016/j.physe.2005.05.031

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