Modal control of thermoplasmonic behavior of nanostructures based on excitation of perfect absorption resonances

Abstract

Controlling the localized heat generation density and temperature profile of nanostructures exploiting perfect absorption of individual resonance modes is reported. The methodology is applied to spherically symmetric nanostructures using the T-matrix method. It is demonstrated that perfect modal splitting of the absorption power at desired wavelengths and individual excitation of the modes provide the ability to localize the generated heat at desired locations, and control the resulting temperature profile in multilayer core–shell structures. By knowing the thermal behavior of individual modes, it is shown that excitation of the perfect absorption modes at desired temperatures can result in compensation for the temperature-rise drop, induced in high-temperature thermoplasmonics due to thermal shift of the resonance frequencies. Much higher temperature rises can be achieved through properly designed thermal mode-coupling schemes. The proposed methodology is very promising for the control of the thermoplasmonic behavior of nanostructures, and the design of much more thermally efficient structures, taking into account the thermally dependent parameters.

Thermo-optical reshaping of SHG emission from dimerall-dielectric nanoresonators

“…Moreover, high-Q states in single cylindrical subwavelength resonators supported 10 −1 SH conversion [36], however tunability of modes and radiation pattern still remains a challenge. On the other hand, such nanoantennas proved their ability for strong optical heating and thermometry due to resonantly enhanced optical absorption [37][38][39]. Owing to strong thermooptical effects [40,41] all-dielectric structures already demonstrated their proficiency in modulation of linear properties of propagating [42,43] and scattered [44] light.…”