Sputtered-silica defect layer in artificial opals: tunability of highly transmitted and reflected optical modes

TL;DR

This paper introduces a controlled sputtering method to create tunable defect layers in silica opals, enabling precise manipulation of optical modes with high transmission and reflection, validated by experiments and simulations.

Contribution

It presents a novel sputtering technique for engineering defect layers in silica opals with tunable optical properties, confirmed by parameter-free simulations.

Findings

Tunable optical modes achieved in silica opal structures

High agreement between experimental data and simulations

Precise control of defect layer thickness and spectral position

Abstract

We propose an original and efficient method to engineer a defect between two well-ordered silica opals by sputtering silica on the top of the first one. As the amount of sputtered silica can be well controlled, it is also the case for the thickness of the layer and consequently for the spectral position of the defect mode. The optical response of these sandwich structures is studied in terms of specular reflection and transmission spectroscopy. Tunable highly transmitted and reflected optical modes are evidenced. The very good agreement between the experimental results and the simulations, run without fitting parameters, demonstrates the almost perfect order of the synthesized structures.