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Magneto-exciton in planar type II quantum dots

K. L. Janssens·B. Partoens·F. M. Peeters
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Abstract

We study an exciton in a type II quantum dot, where the electron is confined in the dot, but the hole is located in the barrier material. The exciton properties are studied as a function of a perpendicular magnetic field using a Hartree-fock mesh calculation. Our model system consists of a planar quantum disk. Angular momentum (l) transitions are predicted with increasing magnetic field. We also study the transition from a type I to a type II quantum dot which is induced by changing the confinement potential of the hole. For sufficiently large magnetic fields a re-entrant behaviour is found from $l_{h}=0$ to $l_{h}\neq 0$ and back to $l_{h}=0$, which results in a transition from type II to type I.

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K. L. Janssens, B. Partoens, F. M. Peeters. 2001-09-14. Magneto-exciton in planar type II quantum dots. https://arxiv.org/abs/cond-mat/0103411

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