A reconfigurable biosensor with different spectral sensitivities could provide new opportunities to increase the label-free selectivity and sensitivity for biomolecules. Here, we propose and numerically demonstrate a phase change chalcogenide material (Ge ₂ Sb ₂ Te ₅ )-based photonic crystal fiber (PCF) sensor for tunable and enhanced refractive index sensing at near infrared (NIR) wavelengths. In order to achieve this, we integrate a thin hybrid sensing layer of Au/Ge ₂ Sb ₂ Te ₅ with D-shaped PCF. By switching the structural phase of Ge ₂ Sb ₂ Te ₅ from amorphous to crystalline, we realize tunable and enhanced refractive index sensing with a large figure of merit (FOM) for the sensing range from 1.35 to 1.40, which covers most known analytes such as proteins, cancer cells, glucose and viruses or DNA/RNA. The obtained average bulk refractive index sensitivity is 17,600 nm/RIU and 8,000 nm/RIU for crystalline and amorphous phase, respectively. The observed large tunable differential response of the proposed sensor offers a promising opportunity to design an assay for the selective detection of higher and lower molecular weight biomolecules through future artificial intelligence-based sensing.

中文翻译：

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使用相变材料的基于光子晶体光纤的可重构生物传感器

具有不同光谱灵敏度的可重构生物传感器可以为提高生物分子的无标记选择性和灵敏度提供新的机会。在这里，我们提出并在数值上展示了一种基于相变硫属化物材料 (Ge ₂ Sb ₂ Te ₅ ) 的光子晶体光纤 (PCF) 传感器，用于在近红外 (NIR) 波长下进行可调和增强的折射率传感。为了实现这一点，我们将 Au/Ge ₂ Sb ₂ Te ₅的薄混合传感层与 D 形 PCF集成在一起 。通过切换Ge ₂ Sb ₂ Te ₅的结构相 从无定形到结晶，我们实现了具有大品质因数 (FOM) 的可调和增强型折射率传感，传感范围从 1.35 到 1.40，涵盖了大多数已知分析物，例如蛋白质、癌细胞、葡萄糖和病毒或 DNA/RNA . 对于结晶和非晶相，获得的平均体折射率灵敏度分别为 17,600 nm/RIU 和 8,000 nm/RIU。所提出的传感器观察到的大的可调差分响应为设计一种通过未来基于人工智能的传感选择性检测较高和较低分子量生物分子的测定提供了一个有希望的机会。