Work

Optical Properties of GeTe/Sb 2 Te 3 ‐Based Phase‐Change Memory Heterostructures Grown by Pulsed Laser Deposition

Year: 2026

Type: article

Abstract: Optical properties of GeTe/Sb 2 Te 3 heterostructures are investigated with emphasis on the combined effects of thickness‐dependent sublayer behavior and interfacial diffusion. Spectroscopic ellipsometry shows that both GeTe and Sb 2 Te 3 thin layers exhibit pronounced, thickness‐dependent dielectric functions that differ substantially from those of thicker films. Consequently, an accurate optical description of nonperiodic heterostructures requires the use of multiple thickness‐specific dielectric‐function models for each constituent material. Interdiffusion at GeTe/Sb 2 Te 3 interfaces leads to the formation of ultrathin Ge–Sb–Te transition layers with compositions close to Ge 2 Sb 2 Te 5 , which are more structurally disordered than thick amorphous Ge 2 Sb 2 Te 5 . The effective refractive index and optical bandgap of the heterostructures span combinations not accessible in the individual materials, demonstrating that heterostructuring enables additional control over optical properties relevant for tunable photonic and optoelectronic applications.

Source: physica status solidi (RRL) - Rapid Research Letters

DOI: 10.1002/pssr.202500492

Authors: Kostiantyn Shportko, Sonja Cremer, Andriy Lotnyk

Institutions: V.E. Lashkaryov Institute of Semiconductor Physics, Leibniz Institute of Surface Engineering

Language: English

Topic: Phase-change materials and chalcogenides

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $4,430

Funder: Deutsche Forschungsgemeinschaft