Application of surface plasmon polariton grating in high sensitive infrared detectors

Abstract

Free electrons in metals can couple with electromagnetic waves and form surface plasmon polariton (SPP) on metal surface, which can effectively couple and bound the radiation energy to the metal surface, leading to significant field enhancement effect in the near field range. Based on the metal periodic structure, the SPP grating can be used to design resonance wavelength flexibly while utilizing the near field enhancement effect, so it has been widely used in the research and development of high sensitive infrared detectors. The charge sensitive infrared phototransistor (CSIP) detector with semiconductor double quantum well structure is a new type of highly sensitivity infrared detector. It utilizes photo-grating effect to realize the multiplier effect of infrared photoelectronic conversion process, therefore, CSIP has the advantages of large tunability, high sensitivity and high photoresponse. This paper reviews the research progress of design and application of SPP grating in CSIP detectors. The coupling physical mechanism, field enhancement effect and polarization conversion efficiency of metal hole array gratings are described. The SPP grating can be optimized to improve the coupling quantum efficiency of CSIP devices. Then, the structure, technological process, fluorescence spectrum, current-voltage ( I - V ) measurement and step-scan spectroscopy are described to demonstrate photoelectric detection performance of CSIP infrared detectors. Finally, the future development and application trend of SPP coupled CSIP devices are prospected.