2025/04/23 by Fouad Bentata, Bentata, Fouad, Arnaud Taute +30
Materials Science · #Applied Physics (physics.app-ph) #FOS: Physical sciences #Liquid Crystal Research Advancements #Materials Science (cond-mat.mtrl-sci) #Optics (physics.optics) #Phase-change materials and chalcogenides
paper · pdf · doi:10.48550/arxiv.2504.16603
openalex publication_date 2025/04/23 · openalex created_date 2025/09/27 · openalex updated_date 2026/07/28
Photonic integrated devices are progressively evolving beyond passive components into fully programmable systems, notably driven by the progress in chalcogenide phase-change materials (PCMs) for non-volatile reconfigurable nanophotonics. However, the stochastic nature of their crystal grain formation results in strong spatial and temporal crystalline inhomogeneities. Here, we propose the concept of spatially-controlled planar guided crystallization, a novel method for programming the growth of optically homogeneous low-loss Sb2S3 PCM, leveraging the seeded directional and progressive crystallization within confined channels. This guided crystallization method is experimentally shown to circumvent the current limitations of conventional PCM-based nanophotonic devices, including a multilevel non-volatile optical phase-shifter exploiting a silicon nitride-based Mach-Zehnder interferometer, and a programmable metasurface with spectrally reconfigurable bound state in the continuum. Precisely controlling the growth of PCMs to ensure optically uniform crystalline properties across devices is the cornerstone for the industrial development of non-volatile reconfigurable photonic integrated circuits.