Hexagonal waveguide arrays written with fs-laser pulses

The linear propagation properties of laser written hexagonal waveguide arrays in fused silica have been studied for the first time. We determine the behavior of the coupling constants for different waveguide separations and for different wavelengths. The high accuracy of these arrays demonstrates the ability to fabricate complex and elongated devices based on evanescently coupled waveguide structures using the fs direct writing approach.