Abstract
Spasers and nanolasers produce a significant amount of heat, which impedes their realizability. We numerically investigate the farfield emission and thermal load in optically pumped spasers with a coupled electromagnetic/thermal model, including additional temperature discontinuities due to interfacial Kapitza resistance. This approach allows to explore multiple combinations of constitutive materials suitable for robust manufacturable spasers. Three main channels of heat generation are quantified: metal absorption at pumping and spasing wavelengths and nonradiative relaxations in the gain material. Out-radiated power becomes comparable with absorption for spasers of realistic dimensions. Two optimized spaser configurations emitting light near 520 nm are compared in detail: a prolate metal-core/gain-shell and an oblate gain-core/metal-shell. The metal-shell design, which with the increasing size transforms into a metal-clad nanolaser, achieves an internal light-extraction efficiency of 22.4%, and stably operates up to several hundred picoseconds, an order of magnitude longer than the metal-core spaser.
Highlights
O ne of the principal problems of the realization of a spaser and metal-clad nanolaser is that there will be strong fields in an absorbing metal component and its vicinity.[1]
The heating of plasmonic nanostructures is interesting in two different aspects: either the heating is a desired effect, for example, for electrothermoplasmonic nanotweezers in microfluidic channels[2] or medical applications of nanoparticles in living tissues,[3] or it threatens the realizability of a device
Ωs is the frequency of surface plasmon oscillations and εh is the dielectric function of the gain host material
Summary
O ne of the principal problems of the realization of a spaser (surface plasmon amplifier using stimulated emission) and metal-clad nanolaser is that there will be strong fields in an absorbing metal component and its vicinity.[1]. We aim to provide practical guidelines for experimenters primarily on two subjects, suggest realistic geometries for individual spasers and give estimates for pumping intensities and durations, as well as expected outradiation and temperatures. This is the first study combining the effects of spatially dependent gain saturation, retardation and radiative losses (i.e., light extraction), heat generation in both metal and gain material, Kapitza resistance, temperature dependences of material properties, and influence of these factors on the temporal evolution of spasing. Saturation field Esat in eq 1 can be expressed as follows from eq 21 in ref 6
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
