Surface Plasmon Polariton (SPP) modes have attracted many minds for over 100 years. Confining light to dimensions
smaller than its propagating wavelength, point towards technological possibilities, such as optical circuitry within ultra
small computer processors or, small biochemical sensors. As for other lasers, surface plasmon lasers (SPL) require gain
and feedback. Yet, quenching of the fluorescence and induced current losses by the metal interface almost proved SPL to
be unattainable. Such impediments were circumvented by a periodic design on the nano scale, which reduced the losses
and maintained gain of a few ten thousands per cm.