OZ Optics’ Ruby and Emerald systems are crystal-based polarization entangled photon sources which integrate the crystals responsible for spontaneous parametric down-conversion into photon pairs inside a self-balanced interferometer engine to generate the wavelength/polarization entanglement in a robust benchtop turn-key device.
Each source comes equipped with a wavelength-stabilized pump laser, a variable optical attenuator, and a temperature controller to fine tune phase matching parameters to realize optimal efficiency. The components are packaged inside a rugged aluminium housing with an on/off power switch and keyed laser control. Signal and Idler photons are available with the pump wavelength removed at separate output ports on the front panel.
Ruby entangled photon sources make use of type-0 down-conversion to generate a broadband biphoton spectrum, with a bandwidth of several tens of nanometers. Emerald entangled photon sources make use of type-2 down-conversion to generate a narrow bandwidth biphoton spectrum, with a bandwidth of a few nanometers. In both cases the interferometer engine ensures photon entanglement regardless of the down-conversion type.