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Electron teleportation between quantum dots using virtual dark exciton

M. Combescot·O. Betbeder-Matibet·V. Voliotis
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Abstract

We here propose a mechanism to teleport electrons between quantum dots through the transformation of a virtual bright exciton into a dark exciton. This mechanism relies on the interactions of two composite bosons: a pair of electrons with opposite spins, trapped in two dots and an electron-hole pair in a free exciton coupled to an unabsorbed pump pulse, which makes it ``bright'' but virtual. This bright exciton first turns ``dark'' by dropping its electron and stealing the trapped electron with opposite spin through an exchange Coulomb process with the trapped pair. In a second step, the dark exciton ``flies'' with its electron to the other dot where it turns bright again, by the inverse process. The ``Shiva diagrams'' for composite boson many-body effects that we have recently introduced, enlighten this understanding.

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M. Combescot, O. Betbeder-Matibet, V. Voliotis. 2006-04-05. Electron teleportation between quantum dots using virtual dark exciton. https://doi.org/10.1209/epl%2Fi2006-10033-9

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