arXiv:1702.02759 · Physical review. B./Physical review. B

Coherent control of the dynamics of a single quantum-dot exciton qubit in a cavity

Antonio de Freitas, L. Sanz, J. M. Villas-Bôas

Published Mar 6, 2017• 11 citations

Abstract

In this paper we demonstrate theoretically how to use an external laser field to control the population inversion of a single quantum dot exciton qubit in a nanocavity. We consider the Jaynes-Cummings model to describe the system, and the incoherent losses were taken into account by using Lindblad operators. We have demonstrated how to prepare the initial state in a superposition of the exciton in the ground state and the cavity in a coherent state. The effects of exciton-cavity detuning, the laser-cavity detunings, the pulse area, and losses over the qubit dynamics are analyzed. We also show how to use a continuous laser pumping in resonance with the cavity mode to sustain a coherent state inside the cavity, providing some protection to the qubit against cavity loss.

DOI: 10.1103/physrevb.95.115110

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