Electro-thermal modelling for plasmonic structures in the TLM method

Abstract

This paper presents a coupled electromagnetic-thermal model for modelling temperature evolution in nano-size plasmonic heat sources. Both electromagnetic and thermal models are based on the Transmission Line Modelling method and are coupled through a nonlinear and dispersive plasma material model. The stability and accuracy of the coupled EM-thermal model is analysed in the context of a nano-tip plasmonic heat source example.

Coupled Electrothermal Two-Dimensional Model for Lightning Strike Prediction and Thermal Modeling Using the TLM Method

“…The results are shown for time step ratios of Δ ℎ /Δ =1, 2, 5, 10 and 100. The results show that actual temperature values in the node are of the same order of magnitude as in the case when Δ ℎ /Δ =1 but that, unlike the studies reported in [16], Δ Δ ℎ should remain the same. Figure.16 examines the plasma distribution for the case when Δ ℎ / Δ =2 and 5.…”

“…Typically due to the slow nature of thermal diffusion compared to the electromagnetic propagation, the thermal time step is much bigger than the EM time step given by (5) (∆t th ≫ ∆t EM ). In our previous work on modeling plasmonic nano-heat structures [16] it was shown that the thermal and EM time steps do not have to be the same and that computational resources can be saved by setting thermal time steps to be up to 600 times bigger than the EM time step for the same level of accuracy and without affecting the stability of the coupled method.…”

Photothermal Effect in Plasmonic Nanotip for LSPR Sensing

“…As the increase in temperature is caused by the interaction of surface plasmons with the metal [48][49][50]. This means that any situation that entails a sufficient amount of such interactions should, in principle, lead to an increase in temperature, causing a temperature based change in refractive index leading to inaccurate measurements of LSPR.…”

“…The process of heat generation depends on the morphology of the metallic structure and the incident wavelength [47]. The heat generation is due to the losses that these surface plasmons travelling along the metal-medium interface encounter in their propagation [48,49]. These losses are known to limit the propagation length of the surface plasmons, thus making them localized, and heating the surrounding medium.…”

A hybrid Boundary Element Unstructured Transmission-line (BEUT) method for accurate 2D electromagnetic simulation

“…Given the sensitivity of the stability of TD-BEM solvers, coupling to the trivially stable UTLM is considered to be a more conservative choice. Finally, UTLM lends itself to the relatively easy inclusion of more exotic media such as meta-materials, cells containing wires, and active media [20]- [23].…”