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arXiv · 0809.1673

Optical Spin Initialization and Non-Destructive Measurement in a Quantum Dot Molecule

Danny Kim·Sophia E. Economou·Stefan C. Badescu·Michael Scheibner·Allan S. Bracker·Mark Bashkansky·Thomas L. Reinecke·Daniel Gammon
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Abstract

The spin of an electron in a self-assembled InAs/GaAs quantum dot molecule is optically prepared and measured through the trion triplet states. A longitudinal magnetic field is used to tune two of the trion states into resonance, forming a superposition state through asymmetric spin exchange. As a result, spin-flip Raman transitions can be used for optical spin initialization, while separate trion states enable cycling transitions for non-destructive measurement. With two-laser transmission spectroscopy we demonstrate both operations simultaneously, something not previously accomplished in a single quantum dot.

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Danny Kim, Sophia E. Economou, Stefan C. Badescu, Michael Scheibner, Allan S. Bracker, Mark Bashkansky, Thomas L. Reinecke, Daniel Gammon. 2008-10-23. Optical Spin Initialization and Non-Destructive Measurement in a Quantum Dot Molecule. https://doi.org/10.1103/physrevlett.101.236804

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