Optimization of IR detection by plasmonic materials


We research methods of improvement of semiconductor infrared detectios for mid and long-wavelength IR range. We considered the methods of enhancement of specific detectivity of detectors utilizing plasmonic materials.



Since resonant frequencies of standard plasmonic materials are in the UV or visible part of the spectrum, we considered strategies to redshift the spectral characteristics to introduce operating wavelengths into infrared range. One of the methods was the use of alternative plasmonic materials (transparent conductive oxides) whose resonant frequencies, in dependence on the doping level, enter the infrared range. Additionally, these particles are coated by high-permittivity dielectric (core shell structures) or fully immersed in it. Another strategy is the use of the so-called designer plasmon structures, where a thin layer of plasmonic material is used with a 2D array of apertures, where the geometry of the unit cell can be used to tune the wavelength of the designer plasmon. Finally, we considered the strategy of the use of metamaterial superabsorbers. It is planned to utilize plasmonic enahcement for uncooled mercury cadmium telluride photoconductive chips produced in our Centre.