Multi-Resonant Tamm-Plasmon-Based Infrared Gas Sensor for Improved Sensitivity and Selectivity

Wavelength-selective thermal emitters provide a cost-effective approach for narrow-band sources in the mid- to long-wave infrared. These emitters have been frequently designed to achieve a desired target emissivity spectra for various applications including thermal camouflage, radiative cooling, and gas sensing. This work will discuss how wavelength-selective thermal emitters can be realized through the use of Tamm plasmon polaritons (TPPs) supported by an aperiodic distributed Bragg reflector (aDBR) for gas sensing applications. The TPP emitter discussed will be composed of an aDBR deposited on a doped cadmium oxide (CdO) film, where layer thicknesses and carrier density are varied to realize a close spectral match to the absorption wavelengths of the target analyte. Through utilizing an aDBR with a tunable plasma frequency CdO film, wafer-scale wavelength-selective emitters can be realized without the use of lithography.