[8p-Z19-1~24] 3.8 Optical measurement, instrumentation, and sensor

▲ [8p-Z19-24] Thermally-induced Spectral Tunability on DBR-based Infrared Emitters

〇(P)David Hernandez¹, Orjan Sele Handegaard^1,2, Naoki Furuhata¹, Tadaaki Nagao^1,2 (1.WPI-MANA (NIMS), 2.Hokkaido Univ.)

Keywords:Infrared sensor, DBR, amorphous Si

In this work, we examined the tunability of the resonance wavelength of DBR-based narrowband perfect absorbers and emitters in the infrared region. The tunability in the refractive index of the component materials in the DBR/LaB₆ emitter system was embodied by the dielectric property change thermally induced by the phase change in Si layers, in the SiO₂/Si-DBR component. By thermally annealing the “as sputtered” structure, we can induce a phase change in a-Si layers to polycrystalline/crystalline Si layers. This change of phase leads to a continuous modification of the optical properties of the DBR structure, which can be used to finely adjust the resonant wavelength of the final device. This strategy can be further extended to many other amorphous materials and provides an alternative way to precisely tune the operation wavelength of DBR structures, thus representing a step forward towards the realization of accurate perfect absorber sensors, thermal emitters among other devices.