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arXiv · 1002.3736

Singlet-triplet transition in a few-electron lateral InGaAs-InAlAs quantum dot

F. Deon·V. Pellegrini·F. Carillo·F. Giazotto·L. Sorba·G. Biasiol·F. Beltram
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Abstract

The magnetic-field evolution of Coulomb blockade peaks in lateral InGaAs/InAlAs quantum dots in the few-electron regime is reported. Quantum dots are defined by gates evaporated onto a 60 nm-thick hydrogen silsesquioxane insulating film. A gyromagnetic factor of 4.4 is measured via zero-bias spin spectroscopy and a transition from singlet to triplet spin configuration is found at an in-plane magnetic field B = 0.7 T. This observation opens the way to the manipulation of singlet and triplet states at moderate fields and its relevance for quantum information applications will be discussed.

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F. Deon, V. Pellegrini, F. Carillo, F. Giazotto, L. Sorba, G. Biasiol, F. Beltram. 2010-03-16. Singlet-triplet transition in a few-electron lateral InGaAs-InAlAs quantum dot. https://doi.org/10.1063/1.3380821

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