Tunable narrowband mid-infrared thermal emitter with a bilayer cavity enhanced Tamm plasmon
- Resource Type
- Article
- Authors
- Zhu, Huanzheng; Luo, Hao; Li, Qiang; Zhao, Ding; Cai, Lu; Du, Kaikai; Xu, Ziquan; Ghosh, Pintu; Qiu, Min
- Source
- Optics Letters; November 2018, Vol. 43 Issue: 21 p5230-5233, 4p
- Subject
- Language
- ISSN
- 01469592; 15394794
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 Ge_2Sb_2Te_5. 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.