Two-photon coherent polarization flipping of confined excitons

TL;DR

This paper demonstrates that picosecond laser pulses can coherently flip the polarization of excitons in quantum dots via a two-photon process, offering a stable method for polarization control.

Contribution

It introduces a novel two-photon polarization flipping technique in quantum dots that is more stable than previous methods.

Findings

Polarization can be coherently flipped with picosecond laser pulses.

The process is related to two-photon Rabi oscillations of a biexciton.

The method is more stable against laser frequency shifts.

Abstract

A two-photon process leading to coherent transitions between the two circularly polarized exciton states in a quantum dot is studied. It is shown that optical flipping of the exciton polarization is possible with picosecond laser pulses. The process is closely related to two-photon Rabi oscillations of a biexciton but it is much more stable against shifts of the laser frequency.