Two-Photon Laser Lithography of Integrated Photonic Structures on MgF2 Substrates

Abstract

Direct two-photon laser lithography has been rapidly developing in recent years due to its unique capabilities for the development, fabrication, and testing of integrated photonics components. The substrate material plays a key role in minimizing optical losses in planar photonic circuits: effective mode confinement requires a high refractive index contrast between the substrate material and the photopolymer used to form the guiding structures. Waveguide structures fabricated by direct two-photon laser lithography on magnesium fluoride (MgF₂) substrates have been experimentally studied and numerically simulated and the effectiveness of their application has been demonstrated.