Self-assembled quantum dot based quantum memory

Irene D’Amico, Brendon W. Lovett

Naoto Horiguchi, T. Futatsugi, Yoshihiro Nakata +1 more

In this paper we report the dynamic properties of InAs self-assembled quantum dots for spectral hole burning memory applications. We measured the time constant of electron transport between InAs self-assembled quantum dots and the n-GaAs substrate by making use of the frequency dependence of the CV signal due to the InAs dots. We obtained a time constant of 2.1 /spl mu/s from experiments. The experimental results are well explained by equivalent circuit calculations and the theoretically calculated CR time constant. The time constant is expected to reach the sub-picosecond range in samples with a 10 nm barrier thickness.

Qu‐Quan Wang, Andreas Müller, Pablo Bianucci +4 more

By using nonlinear resonant optical control and polarized photoluminescence, the authors studied the intensity dependence of exciton spin relaxation and photoluminescence polarization in single self-assembled InGaAs quantum dots. Data from dots with different dipole moments reveal two distinctive channels for polarization memory loss: (i) an external pathway due to carrier escape and capture to and from the wetting layer that is responsible for memory loss increasing with intensity and (ii) an internal loss channel due to intrinsic spin relaxation. The values obtained rule out a universal freezing of exciton spin relaxation in single self-assembled quantum dots related to the wetting layer.

Wolfgang Tittel, Mikael Afzelius, Nicolas Gisin +2 more

Yong Hui Yu