Micro/nanofabrication of heat management materials for energy-efficient building facades

Advanced building facades,which include windows,walls,and roofs,hold great promise for reducing building energy consumption.In recent decades,the management of heat transfer via electromagnetic radiation between buildings and outdoor environments has emerged as a critical research field aimed at regulating solar irradiation and thermal emission properties.Rapid advancements have led to the widespread utilization of advanced micro/nanofabrication techniques.This review provides the first comprehensive summary of fabrication methods for heat management materials with potential applications in energy-efficient building facades,with a particular emphasis on recent developments in fabrication processing and material property design.These methods include coating,vapor deposition,nanolithography,printing,etching,and electrospinning.Furthermore,we present our perspectives regarding their advantages and disadvantages and our opinions on the opportunities and challenges in this field.This review is expected to expedite future research by providing information on the selection,design,improvement,and development of relevant fabrication techniques for advanced materials with energy-efficient heat management capabilities.

Dielectric metasurface evolution from bulk to monolayer by strong coupling of quasi-BICs for second harmonic boosting

2D materials are promising candidates as nonlinear optical components for on-chip devices due to their ultrathin structure. In general, their nonlinear optical responses are inherently weak due to the short interaction thickness with light. Recently, there has been great interest in using quasi-bound states in the continuum (q-BICs) of dielectric metasurfaces, which are able to achieve remarkable optical near-field enhancement for elevating the second harmonic generation (SHG) emission from 2D materials. However, most studies focus on the design of combining bulk dielectric metasurfaces with unpatterned 2D materials, which suffer considerable radiation loss and limit near-field enhancement by high-quality q-BIC resonances. Here, we investigate the dielectric metasurface evolution from bulk silicon to monolayer molybdenum disulfide (MoS2), and discover the critical role of meta-atom thickness design on enhancing near-field effects of two q-BIC modes. We further introduce the strongcoupling of the two q-BIC modes by oblique incidence manipulation, and enhance the localized optical field on monolayer MoS2dramatically. In the ultraviolet and visible regions, the MoS2SHG enhancement factor of our design is 105times higher than that of conventional bulk metasurfaces, leading to an extremely high nonlinear conversion efficiency of 5.8%. Our research will provide an important theoretical guide for the design of high-performance nonlinear devices based on 2D materials.

Nanoscale mapping of optically inaccessible bound-states-in-the-continuum

Bound-states-in-the-continuum(BIC)is an emerging concept in nanophotonics with potential impact in applications,such as hyperspectral imaging,mirror-less lasing,and nonlinear harmonic generation.As true BIC modes are nonradiative,they cannot be excited by using propagating light to investigate their optical characteristics.In this paper,for the 1st time,we map out the strong near-field localization of the true BIC resonance on arrays of silicon nanoantennas,via electron energy loss spectroscopy with a sub-1-nm electron beam.By systematically breaking the designed antenna symmetry,emissive quasi-BIC resonances become visible.This gives a unique experimental tool to determine the coherent interaction length,which we show to require at least six neighboring antenna elements.More importantly,we demonstrate that quasi-BIC resonances are able to enhance localized light emission via the Purcell effect by at least 60 times,as compared to unpatterned silicon.This work is expected to enable practical applications of designed,ultra-compact BIC antennas such as for the controlled,localized excitation of quantum emitters.

Hypoxia induces T-cell apoptosis by inhibiting chemokine C receptor 7 expression:the role of adenosine receptor A2

Hypoxia is a major characteristic of the tumor microenvironment,and its effects on immune cells are proposed to be important factors for the process of tumor immune escape.It has been reported that hypoxia affects the function of dendritic cells and the antitumor function of T cells.Here we discuss the effects of hypoxia on T-cell survival.Our results showed that hypoxia induced apoptosis of T cells.Adenosine and adenosine receptors(AR)are important to the hypoxia-related signaling pathway.Using AR agonists and antagonists,we demonstrated that hypoxia-induced apoptosis of T cells was mediated by A^(2a)and A^(2b)receptors.Furthermore,we are the first,to our knowledge,to report that hypoxia significantly inhibited the expression of chemokine C receptor 7(CCR7)of T cells via the A^(2)R signal pathway,perhaps representing a mechanism of hypoxia-induced apoptosis of T cells.Collectively,our research demonstrated that hypoxia induces T-cell apoptosis by the A^(2)R signaling pathway partly by suppressing CCR7.Blocking the A^(2)R signaling pathway and/or activation of CCR7 can increase the anti-apoptosis function of T cells and may become a new strategy to improve antitumor potential.

In-plane coherent control of plasmon resonances for plasmonic switching and encoding

Considerable attention has been paid recently to coherent control of plasmon resonances in metadevices for potential applications in all-optical light-with-light signal modulation and image processing.Previous reports based on out-ofplane coherent control of plasmon resonances were established by modulating the position of a metadevice in standing waves.Here we show that destructive and constructive absorption can be realized in metallic nano-antennas through in-plane coherent control of plasmon resonances,which is determined by the distribution rule of electricalfield components of nano-antennas.We provide proof-of-principle demonstrations of plasmonic switching effects in a gold nanodisk monomer and dimer,and propose a plasmonic encoding strategy in a gold nanodisk chain.In-plane coherent control of plasmon resonances may open a new avenue toward promising applications in optical spectral enhancement,imaging,nanolasing,and optical communication in nanocircuits.