Effect of quantum dot shape on dynamical dephasing suppression in exciton qubits under applied electric field
We investigate the efficiency of periodic dynamical decoupling of an exciton qubit confined in a self-assembled quantum dot in the presence of an applied electric field. The shape of the quantum dot is found to have a large effect on the excitonic dephasing. It is shown that dynamical suppression of dephasing, through a simple series of equally spaced bit flips, is most efficient for quantum dots that are close to spherical. In addition, compared to the no field case, the presence of an electric field increases the efficiency of the decoupling technique as the quantum dot becomes more oblate. Our calculations show that dephasing can be significantly suppressed in GaAs/AlAs quantum dots suitable for quantum information processing.
quantum dots exciton qubits dynamical decoupling quantum computation