Three-dimensional imaging of direct-written photonic structures

TL;DR

This paper demonstrates the use of third harmonic generation microscopy combined with adaptive optics to non-destructively analyze three-dimensional photonic structures created by femtosecond laser writing, revealing detailed morphology and defects.

Contribution

It introduces a novel application of nonlinear microscopy with adaptive optics for 3D imaging of laser-written photonic devices, providing higher resolution and non-destructive analysis.

Findings

High-resolution 3D imaging of waveguide arrays and gratings

Detection of morphological details invisible to linear microscopy

Effective correction of optical aberrations in complex samples

Abstract

Third harmonic generation microscopy has been used to analyze the morphology of photonic structures created using the femtosecond laser direct-write technique. Three dimensional waveguide arrays and waveguide-Bragg gratings written in fused-silica and doped phosphate glass were investigated. A sensorless adaptive optical system was used to correct the optical aberrations occurring in the sample and microscope system, which had a lateral resolution of less than 500 nm. This non-destructive testing method creates volume reconstructions of photonic devices and reveals details invisible to other linear microscopy and index profilometry techniques.