Nonlocal surface plasmon amplification by stimulated emission of radiation

Abstract

We establish the spaser generation conditions for nonlocal plasmonic lasers and nonlocal plasmonic core-shell lasers based on the full-wave nonlocal Mie theory. Numerical results show that the required gain threshold and the gain refractive index become large generally when the nonlocality or spatial dispersion is taken into account. This tendency can be understood by the analysis with the proposed equivalent permittivity for nonlocal metallic nanoparticles. Since the nonlocality for the compact nanoparticles is quite significant, our study will be of great importance in the design of ultrasmall nanoparticle lasers.

Cooperative effects in spherical spasers: Ab initio analytical model

“…The polarization (50) determines the evolution of the local electromagnetic field, Eq. (16). Its positive frequency part, which originates from the spherical layer boundaries, is found explicitly as follows:…”

“…This experiment stimulated significant interest in theoretical modeling of core-shell spasers, both analytical [10][11][12][13][14][15][16][17][18][19] and numerical [23,24]. The analytical approach suggests different models which take into account the multiple-level structure of the active molecules, their saturation, the nonlocal optical response of the metallic core, and the retardation effect.…”

Lasing Conditions of Transverse Electromagnetic Modes in Metallic-Coated Micro- and Nanotubes

“…These devices can find numerous applications for enhanced spectroscopies, as a way of counteracting the effect of optical losses in different plasmonic devices, or directly as a source of radiation for "lab-on-chip" devices, ultra-dense data storage, or nanolithography [7][8][9][10][11]. Different forms of nanolasers and spasers have been extensively discussed in the literature over the last decades, both from the theoretical [5,[11][12][13][14][15][16][17] and experimental [1-3, 11, 18-25] point of view. There has been studied a wide variety of structures and materials/metamaterials for supporting the spaser/nanolaser as well as different compounds to act as the optical-gain medium.…”

“…Micro- and nanolasers (lasers of micro- or nanoscale dimensions) − and spasers (a type of laser that confines light at subwavelength scales by exciting surface plasmon polaritons) , can be used to provide a controllable source of “on-demand” electromagnetic fields at very small size scales . These devices can find numerous applications for enhanced spectroscopies, as a way of counteracting the effect of optical losses in different plasmonic devices, or directly as a source of radiation for “lab-on-chip” devices, ultradense data storage, or nanolithography. − Different forms of nanolasers and spasers have been extensively discussed in the literature over the last decades, both from the theoretical ,− and experimental − ,,− points of view. There has been studied a wide variety of structures and materials/metamaterials for supporting the spaser/nanolaser as well as different compounds to act as the optical-gain medium.…”

Active Nanophotonics

“…For example, a recent rigorous analysis [105] demonstrates that in this spaser configuration the gain factor required to achieve the lasing threshold is unachievable in practice. In addition, nonlocality and spatial dispersion generally increase the lasing threshold [336]. Indeed, the lack of experiments on the second-order correlation coefficient does not allow to say with confidence in which regime this nanolaser operates.…”