Frequency conversion of coincident photons in a periodically-poled lithium niobate waveguide.

摘要

Quantum communications is a rapidly growing field, but convenient sources of entangled photon pairs are needed for many of the proposed technologies. Though fiber-optic sources are ideal for communication applications, they do not generate photons at appropriate energies for proposed quantum memories. Quantum frequency conversion could increase the flexibility of these sources. If the frequency conversion process is properly managed, the important quantum properties of the photons being converted will not be changed.; Several different schemes have been put forward recently, directed at solving different parts of the quantum frequency conversion problem. All of these schemes involve pump and signal frequencies that are at least 100nm apart in wavelength. However, to convert telecommunication photons to wavelengths appropriate for atomic quantum memories, the pump and signal wavelengths may need to be much closer. There are several challenges that arise from such a configuration, and it is important to explore them. These experiments provide useful information for further development of practical quantum frequency conversion schemes for integration into quantum communication architectures.