Kondo effect in a triangular triple quantum dots ring with three terminals

For a triangular triple quantum dots (TTQDs) ring with three terminals, when lowering one of the dot–lead coupling to realize the left–right (L–R) reflection symmetry coupling, the internal C3vC3v symmetry of the TTQDs is well preserved in the absence of many-body effect for the symmetric distribution of the dot–lead coupling on the molecular orbits. In the presence of Kondo effect, the decrement of one of the dot–lead couplings suppresses the inter-dot hopping. This happens especially for the coupled quantum dot (QD), which decouples with the other two ones gradually to form a localized state near the Fermi level. As a result, the internal dynamic symmetry of the TTQDs ring is reduced to L–R reflection symmetry, and simultaneously, the linear conductance is lifted for the new forming molecular orbit near the Fermi level.