Coupling of molecular vibration and metasurface modes for efficient mid-infrared emission

We demonstrate extraordinarily spectrally selective narrowband mid-infrared radiation via coupling of plasmon resonance and molecular vibration. Absorbance and thermal emittance with resonant peak FWHM ≤ 124 nm at λ = 5.73 μm, corresponding to a Q -factor of ∼92.3 were obtained.