Ten years of spasers and plasmonic nanolasers

Abstract

Ten years ago, three teams experimentally demonstrated the first spasers, or plasmonic nanolasers, after the spaser concept was first proposed theoretically in 2003. An overview of the significant progress achieved over the last 10 years is presented here, together with the original context of and motivations for this research. After a general introduction, we first summarize the fundamental properties of spasers and discuss the major motivations that led to the first demonstrations of spasers and nanolasers. This is followed by an overview of crucial technological progress, including lasing threshold reduction, dynamic modulation, room-temperature operation, electrical injection, the control and improvement of spasers, the array operation of spasers, and selected applications of single-particle spasers. Research prospects are presented in relation to several directions of development, including further miniaturization, the relationship with Bose-Einstein condensation, novel spaser-based interconnects, and other features of spasers and plasmonic lasers that have yet to be realized or challenges that are still to be overcome.

Multipolar Plasmonic Resonances of Aluminum Nanoantenna Tuned by Graphene

“…Here, Δ λ and Δ n are the wavelength shift and refractive index change, respectively. We further quantify the figure of merit ( FOM ), which is defined as the sensitivity divided by FWHM [ 30 , 31 , 32 , 33 ]. For the two peaks of l = 2 and l = 3, the two corresponding FWHMs are 27.5 and 8.5 nm.…”

“…Nevertheless, these fundamental resonant modes of Al nanostructures with poor Q -factor suffer from both strong radiative and non-radiative losses in UV and visible range [ 25 ]. In contrast, multipolar plasmonic high-order resonance modes [ 2 , 26 , 27 ] of Al nanoantennas with high Q -factor due to minimal non-radiative losses have attracted great attention as optical ultrahigh-sensitive sensors [ 28 ], multipolar radiations of quantum emitters [ 29 ], exciton–plasmon coupling [ 30 , 31 ] and nanolasing [ 32 , 33 , 34 ]. The multipolar high-order plasmonic modes have been experimentally investigated by a powerful tool of electron energy loss spectroscopy [ 1 , 2 , 10 ], revealing the spatial and spectral distributions.…”

Light Engineering in Nanometer Space

“…[69] Since then, various types of spaser-based nanolasers with various gain materials and structure shapes have been reported. [70][71][72][73][74] In 2014, the first broadband-tunable, single-mode spaser emitting over the entire visible frequency range was demonstrated. [70] This spaser was composed of InGaN/GaN semiconductor nanorods placed on low-index Al 2 O 3 cladding-capped Ag film, as shown in Figure 4A,B.…”

Lasing at the nanoscale: coherent emission of surface plasmons by an electrically driven nanolaser

“…The implementation of the latter is a great challenge since a significant amount of the surface plasmon field is concentrated in the metal that results in high Joule losses. Nevertheless, the idea of SPASER (from surface plasmon amplification by stimulated emission radiation) [14,15] was proposed inspiring further research for novel truly nanoscale optical sources with efficient pumping schemes. While incoherent sources of surface plasmon polaritons (SPPs) can be relatively easily integrated in a nanophotonic circuitry [1,16,17], the situation is more complicated in the case of coherent SPP sources and amplifiers, since to reach the lasing threshold one has to compensate not only Joule but also radiation losses, which can be quite large due to a small mode volume of the plasmonic cavity [13,18].…”