Narrow-Band Thermal Radiation with Low Directivity by Resonant Modes inside Tungsten Microcavities
Abstract
Narrow-band thermal radiation with low directivity is presented using a periodic array of microcavities on tungsten surfaces. Thermally excited resonant modes inside the microcavities are found to enhance thermal radiation at specific wavelengths. Compared with a flat tungsten surface, thermal radiation from the microcavities has been enhanced by ∼200% at the most enhanced wavelength of λ=5.5 μm. This strong enhancement yields narrow-band thermal radiation with a full width at half maximum of Δ λ=0.59 μm. The enhancement peak positions are well explained using a simple cavity resonator model. By measuring thermal radiation at oblique directions, it is also found that this narrow-band radiation has low directivity.
- Publication:
-
Japanese Journal of Applied Physics
- Pub Date:
- August 2004
- DOI:
- 10.1143/JJAP.43.5253
- Bibcode:
- 2004JaJAP..43.5253K