Simulation of amplified noise characteristics in long-range surface plasmon polariton

Long-range surface plasmon polaritons(LRSPPs) which express characteristics of long distances and low-loss are very hot in the plasmonic devices field. In order to conduct deeply research on low noise amplification of spontaneous emission in the LRSPPs, a waveguide structure and its theoretical model of radiation low-noise amplifier were set up. Then this structure was verified through the simulation calculation of the electromagnetic field distribution, which indicated that short-range surface plasmon polaritons (SRSPPs) are evanescent in metal district by spontaneous radiation, the effective noise power of each unit bandwidth reached to 7.4710-4 fW/Hz, three times to common signal amplifier, which expressed THz signal, the decay of IR140 excited molecules is the process without radiation, in which 100 nm at self-radiative decay rate becomes the inflection point for SRSPPs and LRSPPs, and after the inflection point the radiation process is mainly affected by the spontaneous radiation of LRSPPs.These results not only clear the characteristics of LRSPPs, but also have significant reference value for other plasma models.