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arXiv · 1610.04715

Spin excitations in an all-organic double quantum dot molecule

Max Koole·Jan C. Hummelen·Herre S. J. van der Zant
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Abstract

We realize a strongly coupled double quantum dot in a single all-organic molecule by introducing a non-conjugated bridge in between two identical conjugated moieties. Spin-1/2 Kondo and Kondo enhanced low-energy excitations for respectively the odd and even electron occupation are observed in off-resonant transport. The ground state in the even occupation can be the singlet or the triplet state varying between samples. This observation suggests that both anti-ferromagnetic and ferromagnetic interactions between spins are of the same order of magnitude.

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Max Koole, Jan C. Hummelen, Herre S. J. van der Zant. 2016-10-15. Spin excitations in an all-organic double quantum dot molecule. https://doi.org/10.1103/physrevb.94.165414

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