AI 中文总结
研究沉积态结晶GST薄膜中成分与光学响应关系，通过单一CVD过程避免中间相转变，建立了两者直接关联，发现成分梯度影响光学行为，飞秒激光可实现空间选择性调谐，确立其为光子元件平台。
AI 中文摘要
相变Ge_Sb_Te（GST）材料通过结构转变表现出显著的光学对比度和可调性，适用于多种光子和光电子应用。GST材料经历可逆的非晶-晶相转变，在此期间，晶相中的折射率和消光系数在宽光谱范围内显著增加。然而，尚未建立沉积态结晶GST薄膜中局部成分、晶体微观结构和宽带光学响应之间的系统相关性。本文报道了在单一CVD过程中，对沉积态结晶GST薄膜（包括Ge3Sb2Te6、Ge2Sb2Te5和GeSb2Te4）中成分分辨的光结构性质关系进行的系统研究，避免了中间相转变。这使得能够直接关联成分、微观结构、形态和400-1700nm范围内的宽带光学响应。具体而言，成分梯度导致吸收最小值从815.9nm移至889.8nm，强度变化5.9倍，反映了光学行为对成分和微观结构的强烈依赖性。还表明飞秒激光辐照能够实现光学响应的空间选择性调谐。这些发现将结晶GST薄膜确立为宽带可调谐、空间可编程光子元件的平台，可通过成分设计和局部激光加工进行控制。
英文摘要
Phase change Ge_Sb_Te (GST) materials exhibit pronounced optical contrast and tunability driven by structural transformations, enabling a diverse range of photonic and optoelectronic applications. GST materials undergo reversible amorphous crystalline phase transitions during which the refractive index and extinction coefficient increase significantly in the crystalline phase across a broad spectral range. However, a systematic correlation between local composition, crystalline microstructure, and broadband optical response within as deposited crystalline GST films has not been established, particularly for films spanning various compositions within a single growth process and in the absence of amorphous-crystalline transitions. Here, we report a systematic study of composition resolved optostructural property relationships in as-deposited crystalline GST films spanning Ge3Sb2Te6, Ge2Sb2Te5, and GeSb2Te4 within a single CVD process, avoiding intermediate phase transitions. This enables direct correlations between composition, microstructure, morphology, and broadband optical response across 400-1700 nm. Specifically, the compositional gradient results in a shift of the absorption minimum from 815.9 nm to 889.8 nm, accompanied by a 5.9 fold change in the intensity, reflecting the strong dependence of optical behavior on composition and microstructure. We further show that femtosecond laser irradiation enables spatially selective tuning of the optical response. These findings establish crystalline GST films as a platform for broadband-tunable, spatially programmable photonic elements, controllable through both compositional design and localized laser processing.
DOI：10.1016/j.mseb.2026.119731
