Patent ID: 8873133

Claim:
A system for conversion or amplification using quasi-phase matched four-wave-mixing, comprising: a first radiation source providing a pump radiation beam, a second radiation source providing a signal radiation beam, a bent structure arranged to receive the pump radiation beam and the signal radiation beam, wherein a radiation propagation portion of the bent structure is made of a uniform Raman-active or uniform Kerr-nonlinear material said radiation propagation portion comprising a dimension taking into account the spatial variation of the Raman susceptibility or Kerr susceptibility along the radiation propagation portion as experienced by radiation travelling along the bent structure to obtain quasi-phase-matched four-wave-mixing in the radiation propagation portion, the dimension being substantially inversely proportional to a linear phase mismatch for four-wave-mixing, and an outcoupling radiation propagation portion of the bent structure that couples out an idler radiation beam generated in the bent structure.