Quantum dynamics of exciton lasers

Alberto Pretel, John Henry Reina, W.R. Aguirre-Contreras

柄律 玄

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

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.

Hyun Byung-Ryoo

Jeremy J. Baumberg, Albert P. Heberle, Klaus Köhler +1 more

We report the coherent control of excitons in quantum wells with pairs of 150-fs infrared pulses. Oscillations in the exciton density versus inter-pump-pulse separation, which correspond to the resonant transition energy, yield new insight into coherent exciton dynamics when their phase is analyzed. We demonstrate that these oscillations are caused when the second laser pulse destroys or enhances excitons that were created by the first pulse. The coherent carrier destruction generates ultrafast exciton dynamics that are not limited by the linewidth of the optical transition.

A. Suzuki, Tetsuo Kodera, Tomoyuki MIYAZAWA +5 more

We demonstrate a coherent manipulation of both exciton and biexciton in an InAs quantum dot operating at a telecommunication band. Telecommunication laser diode successfully drives the coherent system and enables to probe the carrier dynamics.