A two-dimensional photonic crystal for surface temperature mapping

Abstract

A two-dimensional photonic band gap structure is proposed for surface temperature readingof objects. Optical properties of GaAs are utilised in the design and simulation of the device since GaAs is nearly transparent and lossless in the chosen infrared region, and also has areasonably high dielectric constant of 11.4. The structure consists of a triangular lattice of air holes etched into a GaAs slab, with a lattice constant, a, of 0.382 m, including one linearwaveguide and three isolated point defects with radii 0.51a, 0.54a, and 0.57a, espectively. The operational principle of the device is based on guiding and vertically filtering out threepre-selected specifically tuned wavelengths through the corresponding point defects. It isshown that having processed the intensities of these wavelengths, obtained from each defect,in accordance with the blackbody radiation characteristics and the transmission properties ofthe device, the temperature reading of the target in concern is obtained.