Tuning infrared absorption in hyperbolic polaritons coated silk fibril composite

Advanced textiles for thermal management give rise to many functional applications and unveil a new frontier for the study of human thermal comfort.Manipulating the coated quasi-particles between the composite components offers a platform to study the advanced thermoregulatory textiles.Here,we propose that coating the hyperbolic polariton can be an effective tool to tune infrared absorption in hexagonal boron nitride-coated silk composite.Remarkably,we achieve significant tuning of the infrared absorption efficiency of silk fibrils through the designed hexagonal boron nitride film.The underlying mechanism is related to resonance coupling between hyperbolic phonon polaritons.We find a notably high infrared absorption efficiency,nearly 3 orders larger than that without hBN coating,which can be achieved in our composite system.Our results indicate the promising future of advanced polariton-coated textiles and open a pathway to guide the artificial-intelligence design of advanced functional textiles.

Erratum to“Designing thermal demultiplexer:Splitting phonons by negative mass and genetic algorithm optimization”

Equations(8)and(9)in the original paper[Chin.Phys.B 30036301(2021)]are corrected.

Designing thermal demultiplexer: Splitting phonons by negative mass and genetic algorithm optimization

We propose the concept of thermal demultiplexer, which can split the heat flux in different frequency ranges intodifferent directions. We demonstrate this device concept in a honeycomb lattice with dangling atoms. From the view ofeffective negative mass, we give a qualitative explanation of how the dangling atoms change the original transport property.We first design a two-mass configuration thermal demultiplexer, and find that the heat flux can flow into different ports incorresponding frequency ranges roughly. Then, to improve the performance, we choose the suitable masses of danglingatoms and optimize the four-mass configuration with genetic algorithm. Finally, we give out the optimal configuration witha remarkable effect. Our study finds a way to selectively split spectrum-resolved heat to different ports as phonon splitter,which would provide a new means to manipulate phonons and heat, and to guide the design of phononic thermal devices inthe future.

Transport in electron–photon systems

We review the description and modeling of transport phenomena among the electron systems coupled via scalar or vector photons.It consists of three parts.The first part is about scalar photons,i.e.,Coulomb interactions.The second part is with transverse photons described by vector potentials.The third part is onϕ=0 or temporal gauge,which is a full theory of the electrodynamics.We use the nonequilibrium Green’s function(NEGF)formalism as a basic tool to study steady-state transport.Although with local equilibrium it is equivalent to the fluctuational electrodynamics(FE),the advantage of NEGF is that it can go beyond FE due to its generality.We have given a few examples in the review,such as transfer of heat between graphene sheets driven by potential bias,emission of light by a double quantum dot,and emission of energy,momentum,and angular momentum from a graphene nanoribbon.All of these calculations are based on a generalization of the Meir–Wingreen formula commonly used in electronic transport in mesoscopic systems,with materials properties represented by photon self-energy,coupled with the Keldysh equation and the solution to the Dyson equation.