Optically Stimulated andSpontaneously Generated Electron SpinCoherence inQuantuin Dots

Guy Lewis Steel, A. S. Bracker, J. Sham, SanDiego LaJolla

Published Jan 1, 2005• 0 citations

Abstract

Wereport theobservation oflong-lived quantum beats inquantum dots(ensemble andsingle) duetoelectron spincoherence, resulting fromstimulated Ramantransition aswell asspontaneous radiative decay ofthetrion state. © 2004Optical Society ofAmerica OCIScodes:(300.6240) Coherent transient spectroscopy; (300.6420) Nonlinear spectroscopy; (300.6470) Semi- conductors spectroscopy Theelectron spininquantumdots(QD's) isapromising candidate foraqubit forquantuminformation processing duetoitslonglifetime andanticipated robust coherence (1). Suchstructures havefeatured in numerous proposals using ultrafast optical coupling tocoherently manipulate thespinstates. Inthis paper, wedemonstrate suchcoupling andfindanewcontribution tothecoherence observed through quantum beats.

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