Fig. 3: All-optical control over PS waveguide.

a Schematic illustration of creating a PS waveguide eigenstate. The wide pump (red) and idler (green) beams are focused on the crystal with the PS waveguide structure through the wedged adiabatic converter, generating the |\({\psi }_{+}\)〉 eigenstate. The eigenstate |\({\psi }_{+}\) 〉 is then guided through the PS waveguide structure, resulting in a decreased scattered |\({\psi }_{-}\)〉. b Near field image of the signal field, where most of the power is guided through the structure. c Same as b but with a path difference of 3 μm in the adiabatic converter stage. d Corresponding experimental cross-section. Blue curve corresponds to the results presented in (b), while the orange curve corresponds to the results presented in (c). e–g Simulation results of the experimental results in panels (b–d).