Exciton–polariton ultrafast condensate dynamics, devices and circuits

Exciton–polariton ultrafast condensate dynamics, devices and circuits

 

Strong coupling has been studied in atomic physics since the first demonstrations of vacuum Rabi splitting which manifests the new dressed eigenstates of the system. In semiconductors, these dressed states correspond to new quasi-particles when quantum well excitons are strongly coupled to a microcavity mode. Exciton-polaritons which emerge from this strong coupling have a unique combination of extremely low effective mass and strong polariton- polariton interactions which enable observations of a wide range of physical phenomena including strong parametric scattering, and high-temperature Bose-Einstein condensation (BEC).
Optical manipulation of exciton-polariton BEC was recently achieved by potentials created by repulsive interaction between excitons. The switching speed of these potentials based on carrier generation, however, is limited by the carrier dynamics, preventing fast manipulation and characterization of the condensate. Our demonstration of the dynamic Stark shift of exciton-polaritons can provide a fast-switching and density-independent technique of manipulating and reconstructing the state of the condensate using quantum tomography.
This approach may also enable the interaction of quantum vortices of the condensate with orbital angular momentum of light for storing and processing quantum information.