Ultralow radiative heat flux by Anderson localization in quasiperiodic plasmonic chains

TL;DR

The paper addresses how disorder affects radiative heat transfer in a many-body photonic system by analyzing a 1D quasiperiodic chain of plasmonic InSb nanoparticles with modulation strength $\eta$. It employs a coupled-dipole Green's-function framework to connect eigenmodes to transport via the transmission coefficient $\tau_{1N}(\omega)$ and spectral conductance $h_{1N}(\omega)$, revealing an Anderson localization transition. This transition yields ultralow radiative conductance in the localized phase, with suppression governed by $d$, $\Gamma$, and $\eta$, and distinguished by localized bulk modes and topological edge modes identified through eigenfrequencies $\omega_l$ and end-site weights $\mathcal{S}_l$. The results offer a mechanism to tailor nanoscale heat flow through engineered disorder and point to extensions to phonon-polaritons for practical heat management at the nanoscale.

Abstract

Anderson localization, arising from wave interference in disordered systems, profoundly hinders energy transport, yet its impact on radiative heat flux in many-body thermophotonic systems remains unclear. Here, we demonstrate a three-order-of-magnitude suppression of radiative heat transfer, resulting in ultralow radiative heat transfer, in a one-dimensional quasiperiodic chain of plasmonic nanoparticles. This suppression in radiative heat transfer is directly correlated with mode localization, as revealed by the mode decomposition of the transmission coefficient, which serves as evidence of Anderson localization. Furthermore, we elucidate the dependence of radiative thermal conductance reduction on interparticle spacing and material damping rates, uncovering the interplay between intrinsic Ohmic losses, mode localization, and long-range many-body interactions. Our findings advance the understanding of wave-mediated thermal transport in disordered photonic structures and suggest strategies for tailoring nanoscale heat management via engineered disorder.

Figures (6)

• Figure 1: Sketch of one-dimensional quasiperiodic plasmonic dipole array.a A finite chain of indium antimonide (InSb) nanoparticles with identical radii $a$, exhibiting Aubry-André-Harper modulation in the interparticle spacing $d_n$. The inset illustrates the modulation profile and the distribution of spacings with black dots indicating the spacing between the $n^{\text{th}}$ and $n+1^{\text{th}}$ particles. b The chain is simplified as an array of dipoles with many-body interactions incorporated. The interaction strength is adjustable by modifying the nanoparticle spacings within the array. These interactions are decoupled into two distinct polarizations: longitudinal ($x$) and transverse ($y$ and $z$). In the thermal energy transport model, the first nanoparticle ( marked in red) is heated to a temperature of $T+\Delta T$, while the other nanoparticles (marked in blue) and the background are fixed at a constant temperature of $T$.
• Figure 2: Emergent localized eigenmodes in quasiperiodic plasmonic arrays.a, b Inverse participation ratio (IPR) of different eigenmodes as a function of corresponding eigenfrequencies and quasiperiodic modulation strength $\eta$ for longitudinal and transverse polarizations, respectively. c Schematic of array configurations at three modulation strengths: $\eta=0$, $\eta=0.3$, and $\eta=0.6$. d-i Spatial distributions of effective extinction efficiency $Q_n$ for longitudinal (d, f, h) and transverse (e, g, i) polarizations at the corresponding modulation strengths. The parameters for the calculations are set as $N=100$, $a=20$ nm, $d=200$ nm, $\beta=(\sqrt{5}-1)/2$ and $\phi=0$. Absorptive loss can impede the observation of band modes through optical field excitation due to the skin effect of metallic nanoparticles. Thus, a small Ohmic damping of $\Gamma=1\times 10^{9}$ rad s$^{-1}$ is chosen to improve the resolution here.
• Figure 3: Transmission spectra of quasiperiodic plasmonic arrays.a Illustration of transmission channels between the first and final dipoles for a specific frequency in relation to the Anderson localization transition. Before the localization transition ($\eta<\eta_\text{c}$), plasmonic dipoles form an extended collective wave as sketched by the black curve, while after the localization transition ($\eta>\eta_\text{c}$), a localized collective wave emerges, as denoted by the gray-shaded curve. b-g Spectral transmission coefficient $\tau_{1N}$ between dipoles at the chain's two ends as a function of modulation strength $\eta$ for longitudinal (b, d, f) and transverse (c, e, g) polarizations with different Ohmic damping rates: (b, c) $\Gamma=1\times 10^{12}$ rad s$^{-1}$, (d, e) $\Gamma=5\times 10^{10}$ rad s$^{-1}$, and (f, g) $\Gamma=1\times 10^{9}$ rad s$^{-1}$. Other parameters are the same with those in Fig. \ref{['fig:2']}.
• Figure 4: Radiative heat transport through eigenchannels.a-c Eigenfrequency spectrum $\omega_l$ colored with localization index $\mathcal{S}_l$, spectral response function $\mathcal{R}(\omega)$, and spectral thermal conductance $h_{1N}(\omega)$ between nanoparticles at the chain's two ends for the longitudinal polarization at three given modulation strengths of $\eta=0$, $\eta=0.3$, and $\eta=0.6$, respectively. The radii of the nanoparticles are specified as a$a=50$ nm, b$35$ nm, and c$20$ nm. The star markers denote the cases of excited frequencies discussed in d. d Spatial contours of the radiated electric-field energy density $u$, evaluated at a height of 30 nm above the array for the longitudinal polarization, corresponding to the cases in c. The other parameters include $N=20$, $d=200$ nm, $T=300$ K, $\beta=(\sqrt{5}-1)/2$, and $\phi=0$.
• Figure 5: Radiative heat transfer mediated by many-body interactions.a-f Spectral thermal conductance $h_{1N}(\omega)$ for the integrated contributions of longitudinal and transverse polarizations as a function of the mean interparticle distance $d$ at fixed modulation strengths of $\eta=0$ (a, d), $\eta=0.3$ (b, e), and $\eta=0.6$ (c, f) with damping rates of a-c$1\times 10^{9}$ rad s$^{-1}$ and d-f$1\times 10^{12}$ rad s$^{-1}$. g-l Total thermal conductance $\sigma_{1N}$ and modulation ratio $\varphi$ versus interparticle distance $d$, evaluated for three modulation strengths and damping rates. The inset in (j) gives the baseline case of two-body thermal conductance. The black dashed line indicates $\varphi=1$. All calculations assume $N=20$, $a=20$ nm, $d=200$ nm, $T=300$ K, $\beta=(\sqrt{5}-1)/2$, and $\phi=0$.