Model of the enhanced circular dichroism in the excited states emission from p-doped InAs/GaAs quantum dots

Gabriela M. Slavcheva, Matthew W. Taylor, Peter Spencer +3 more

Gabriela M. Slavcheva, Matthew W. Taylor, Peter Spencer +3 more

Gabriela M. Slavcheva

A new generalised group-theoretical approach, based on master Maxwell-pseudospin equations, is proposed to explain recently observed enhanced circular dichroism in the excited state emission from p-doped quantum dot ensembles under resonant circularly polarised excitation into hot trion states, herein referred to as "spin-filtering effect". The theory agrees remarkably well with polarised time-resolved photoluminescence experiments, yielding largely unknown inter- and intra-shell spin relaxation time scales. This approach allows to predict optimum pulse parameters for control of spin dynamics, which will enable exploitation of the effect in all-optical spin-based quantum technologies.

Yoan Léger, Lucien Besombes, L. Maingault +1 more

S. Cortez, O. Krebs, S. Laurent +7 more

We show that the spin state of the resident electron in an n-doped self-assembled InAs-GaAs quantum dot can be written and read using nonresonant, circularly polarized optical pumping. A simple theoretical model is presented and accounts for the remarkable dynamics producing counterpolarized photoluminescence.

Dou Xiu-Ming, Baoquan Sun, Chang Xiu-Ying +4 more

We report on the single photon emission from single InAs/GaAs self-assembled Stranski–Krastanow quantum dots up to 80 K under pulsed and continuous wave excitations. At temperature 80 K, the second-order correlation function at zero time delay, g (2) (0), is measured to be 0.422 for pulsed excitation. At the same temperature under continuous wave excitation, the photon antibunching effect is observed. Thus, our experimental results demonstrate a promising potential application of self-assembled InAs/GaAs quantum dots in single photon emission at liquid nitrogen temperature.