Fast electroholographic wavelength selective switching implemented in a slab waveguide

We present wavelength selective switching with a rise time of 25 ns implemented in a slab waveguide constructed in a KLTN:Cu crystal. The waveguide was fabricated by implantations of alpha particles at 2.1 MeV which produced a 0.5 μm thick cladding layer with reduced refractive index at 4.5 μm underneath the crystal surface. This demonstrates the feasibility of implementing electroholography in waveguides maintaining the performance obtained in bulk crystals, providing in potential the basis for constructing integrated photonic circuits which incorporate interconnected electroholographic wavelength selective switches and electrical wavelength tuning devices for employing wavelength addressing routing schemes in computer networks, in particular for relieving the bandwidth bottlenecks in data center networks.