Interlaboratory study on Sb₂S₃ interplay between structure, dielectric function, and amorphous-to-crystalline phase...

Area of Science:

• Materials Science
• Optoelectronics
• Nanotechnology

Background:

• Antimony sulfide (Sb2S3) is a promising phase-change material with tunable band gap (2.2-1.6 eV) for optical applications.
• Its optical properties vary significantly between amorphous and crystalline phases, offering potential for reconfigurable devices.

Purpose of the Study:

• To investigate the amorphous-to-crystalline transformation in Sb2S3 under thermal and optical stimuli.
• To analyze the relationship between structural changes and optical contrast.
• To identify distinct crystallization regimes and their optical characteristics.

Main Methods:

• Interlaboratory study involving Raman and ellipsometric spectroscopy.
• Statistical analysis of spectroscopic data.
• Characterization of optical contrast (Δn) and dielectric function.

Main Results:

• Two crystallization regimes identified: Type-I (250-300°C) with spherulitic structures and Δn ~ 0.4, and Type-II (300-350°C) with bended spherulitic structures and Δn ~ 0.2.
• Distinct dielectric functions observed for each crystallization type.
• Optical contrast tunable with crystallization conditions.

Conclusions:

• The study elucidates the dual-regime crystallization behavior of Sb2S3.
• Findings provide a foundation for designing reconfigurable nanophotonic devices, including phase modulators and nanoantennas.
• Precise control over crystallization enables tailored optical properties for advanced photonic applications.