AUTHORS: Dionisis Stefanatos, Vasilios Karanikolas, Nikos Iliopoulos, Emmanuel Paspalakis
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ABSTRACT: We propose and analyze fast spin initialization for a quantum dot in the Voigt geometry by placing it near a graphene layer. We show that high levels of fidelity, significantly larger than in the case of the quantum dot without the layer, can be quickly obtained due to the anisotropy of the enhanced spontaneous decay rates of the quantum dot near the graphene layer. We initially obtain these results by using a continuous wave optical field with constant control amplitude. We also use state of the art numerical optimal control to find the time-dependent electric field which maximizes the final fidelity for the same short duration as in the previous case. A better fidelity is obtained with this method
KEYWORDS: Quantum control, numerical optimal control, quantum dot, spin initialization, Voigt geometry, optical pumping, spin dynamics
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