Opt Lett. 2018 Nov 1;43(21):5230-5233. doi: 10.1364/OL.43.005230.
A narrowband thermal emitter exhibits higher energy efficiency and sensitivity in molecule sensing and other mid-infrared (MIR) spectral range applications compared to a blackbody emitter. Most narrowband thermal emitters involving surface plasmons have a relatively low quality factor (Q-factor) and require complex fabrication processes. Here we propose a bilayer cavity-enhanced Tamm plasmon (TP) structure with a high/low refractive index bilayer sandwiched between a metal and distributed Bragg reflector (DBR) to achieve an enhanced Q-factor and maintain higher emittance over a conventional pure DBR-metal TP structure-based emitters. The large optical thickness of the high/low index bilayer cavity aids in increasing the Q-factor (∼172 for emission) of the cavity resonance. Furthermore, a tunable Q-factor is achieved (Q from 172 to 47 for emission) by incorporating phase-changing material GeSbTe. This easy-to-fabricate and tunable high Q-factor emitter is competent as a narrowband MIR light source in molecule sensing, typically gas sensing applications.
窄带热发射器在分子传感和其他中红外 (MIR) 光谱范围内的应用中比黑体发射器具有更高的能量效率和灵敏度。大多数涉及表面等离激元的窄带热发射器的品质因数 (Q 因子) 相对较低，并且需要复杂的制造工艺。在这里，我们提出了一种具有高/低折射率双层的双层腔增强 Tamm 等离子体 (TP) 结构，该双层夹在金属和分布式布拉格反射器 (DBR) 之间，以实现增强的 Q 因子，并保持高于传统基于纯 DBR-金属 TP 结构的发射器的发射率。高/低折射率双层腔的大光学厚度有助于增加腔共振的 Q 因子（对于发射约为 172）。此外，通过引入相变材料 GeSbTe 实现了可调 Q 因子（对于发射 Q 因子从 172 到 47）。这种易于制造和可调谐的高 Q 因子发射器可作为分子传感中，通常是气体传感应用中的窄带 MIR 光源。
