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arXiv · 1506.02439

Type II InAs/GaAsSb Quantum Dots: Highly Tunable Exciton Geometry and Topology

José M. Llorens·Lukasz Wewior·Edson R. Cardozo de Oliveira·José M. Ulloa·Antonio D. Utrilla·Álvaro Guzmán·Adrián Hierro·Benito Alén
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Abstract

External control over the electron and hole wavefunctions geometry and topology is investigated in a p-i-n diode embedding a dot-in-a-well InAs/GaAsSb quantum structure with type II band alignment. We find highly tunable exciton dipole moments and largely decoupled exciton recombination and ionization dynamics. We also predicted a bias regime where the hole wavefunction topology changes continuously from quantum dot-like to quantum ring-like as a function of the external bias. All these properties have great potential in advanced electro-optical applications and in the investigation of fundamental spin-orbit phenomena.

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José M. Llorens, Lukasz Wewior, Edson R. Cardozo de Oliveira, José M. Ulloa, Antonio D. Utrilla, Álvaro Guzmán, Adrián Hierro, Benito Alén. 2015-06-08. Type II InAs/GaAsSb Quantum Dots: Highly Tunable Exciton Geometry and Topology. https://doi.org/10.1063/1.4934841

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