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arXiv · 1401.6331

Mechanically induced pseudo-magnetic fields in the excitonic fine structures of droplet epitaxial quantum dots

Shun-Jen Cheng·Yu-Huai Liao·Pei-Yi Lin
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Abstract

We present numerical investigations based on the Luttinger-Kohn four-band $k \cdot p$ theory and, accordingly, establish a quantitatively valid model of the excitonic fine structures of droplet epitaxial GaAs/AlGaAs quantum dots under uni-axial stress control. In the formalisms, stressing a photo-excited quantum dot is equivalent creating a pseudo-magnetic field that is directly coupled to the pseudo-spin of the exciton doublet and tunable to tailor the polarized fine structure of exciton. The latter feature is associated with the valence-band-mixing of exciton that is especially sensitive to external stress in inherently unstrained droplet epitaxial GaAs/AlGaAs quantum dots and allows us to mechanically design and prepare any desired exciton states of QD photon sources prior to the photon generation.

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Shun-Jen Cheng, Yu-Huai Liao, Pei-Yi Lin. 2014-12-19. Mechanically induced pseudo-magnetic fields in the excitonic fine structures of droplet epitaxial quantum dots. https://doi.org/10.1103/physrevb.91.115310

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