Investigation of Sb2S3 crystalline micro-devices for photonics applications

The Institute for Light and Matter (Institut Lumière Matière - iLM) is a joint CNRS-University of Lyon 1 research unit located on the Lyon Tech La Doua campus.

With more than 300 employees, including a hundred doctoral students and post-docs, the iLM is a major player in physics and chemistry research in the Auvergne Rhône Alpes region, internationally recognized for the excellence of its research.

The growing energy demands of electronic computing have led researchers to explore alternatives like optical computing, which offers low power use, and high throughput. Traditional optical systems are bulky and costly, limiting their practicality. Phase Change Materials (PCM) emerged as promising tools for non-volatile refractive index modulation [1,2], but common PCM (VO₂, GST…) suffer from high optical absorption. New PCMs (Sb₂S₃, Sb₂Se₃) provide strong tunability with low absorption in the near-infrared, making them highly promising for photonics chip integration [3].

Project:

In this project, we aim to investigate the guided planar crystal growth in microchannel that we recently studied in collaboration with the Institute of Nanotechnology in Lyon [4]. The objective is to understand the crystal growth orientation as a function of the fabricated process flow. For that purpose, we will compare microstructural characterization in the fabricated devices to a bulk crystal using Raman spectroscopy [5] and X-ray diffraction measurements [6].

Missions:

The internship student will be in charge of the device characterization using optical microscopy and Raman spectroscopy for both micro-devices and bulk crystal. Furthermore, he/she will perform X-ray diffraction on the bulk crystal to identify the crystal orientation. We want to establish mathematical empirical equations describing mode intensities as a function of crystal orientation and light polarization for comparison to literature and devices characterization. The influence of the layer annealing will be also potentially studied.

At the end of the internship, the master student will acquire skills on X-Ray diffraction and Raman spectroscopy and will have a good knowledge on crystalline materials.

[1] W. Dong et al., Adv. Funct. Mater. 29, 1806181 (2019). [link]

[2] M. Delaney et al., Adv. Funct. Mat. 30, 2002447 (2020).[link]

[3] C. Laprais, et al. Advanced Optical Mat. 12, 240214 (2024)  [link]

[4] F. Bentata et al., Advanced Materials, e06609 (2025) [link]

[5] A. Gassenq et al. J. Raman Spectrosc. 53, 755 (2022) [link]

[6] A. Gassenq et al., J. Appl. Phys. 121, 055702 (2017) [link]

Experimental skill, data treatment, X-ray diffraction, Raman spectroscopy, photonics...