Quantum optical system

Abstract

An optical system comprising a charged quantum dot having, a charged carrier, first and second ground state levels and a plurality of excited state levels, the first and second ground state energy levels having different spin states such that the said charged carrier cannot transfer between the first and second ground state energy levels without changing its spin state, the system further comprising a controller adapted to control a first radiating beam with energy not more than 100 micro-eV from a first transition within said quantum dot from a first ground state level to a selected excited state level from the plurality of excited state levels to, the system being adapted to enhance the decay rate of a second transition within said quantum dot from the selected excited state level to a second ground state level, but not a first transition, such that a photon is produced due to scattering of a photon from the first radiating beam, wherein the controller is adapted to irradiate the quantum dot with the first radiating beam for a time longer than the radiative lifetime of the selected excited state to produce just one photon, and wherein the first radiating beam comprises at least one pulse.

Dependencies are inferred from the claim text.