Article
Materials Science, Multidisciplinary
Chang Yang, Hao Guo, Huicong Chang, Yanchen Qu, Lin Xiao
Summary: In this study, a metamaterial-based infrared camouflage and radar compatible stealth structure is designed and fabricated. Different frequency selective surfaces (FSS) with varying infrared emissivity values are arranged into a visible camouflage pattern. The structure achieves high infrared camouflage and radar absorption capabilities, with the radar waves transmittance above 98% and absorption rate greater than 90% from 4.5 GHz-18 GHz.
OPTICAL MATERIALS EXPRESS
(2023)
Article
Multidisciplinary Sciences
Huanzheng Zhu, Qiang Li, Chenning Tao, Yu Hong, Ziquan Xu, Weidong Shen, Sandeep Kaur, Pintu Ghosh, Min Qiu
Summary: This paper demonstrates a camouflage method that covers a wide range of frequencies based on multilayer and metasurface technologies, achieving multispectral camouflage and efficient radiative cooling simultaneously.
NATURE COMMUNICATIONS
(2021)
Review
Biochemistry & Molecular Biology
Hieu D. Nguyen, Loi H. Do
Summary: This review presents the general approaches for taming glutathione in metallodrug therapy and discusses their strengths and limitations. The perspectives on developing practical solutions that are effective and clinically relevant are also offered.
CURRENT OPINION IN CHEMICAL BIOLOGY
(2022)
Article
Materials Science, Multidisciplinary
Zifu Xu, Longqiu Li, Xiaocong Chang, Yu Zhao, Wuyi Wang
Summary: Conventional methods for manipulating heat flow are limited by a balance between tunable capability and thermal conductivity, while a novel approach using reconfigurable thermal metamaterial is proposed to enhance the responsiveness and efficiency of thermal fields. Precise and reconfigurable thermal coding/decoding information transmission is demonstrated with multiple thermal particles regulating units.
APPLIED MATERIALS TODAY
(2021)
Article
Optics
Kaihua Zhang, Yanfen Xu, Xiaohu Wu, Kun Yu, Yufang Liu
Summary: An improved method for measuring spectral emissivity by modulating the surrounding radiation is proposed in this study. A measurement apparatus is constructed and validated, and the results demonstrate the reliability and accuracy of the proposed method.
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
(2022)
Article
Environmental Sciences
Jianwei Huang, Shanjun Liu, Wenfang Liu, Chunju Zhang, Shuiping Li, Min Yu, Lixin Wu
Summary: Different types of fracturing modes exhibit different trends in thermal infrared (TIR) radiance variation. Experimental observations show that extensional fissures lead to increased radiance with a local peak in the 8.0-9.7 µm range, while local bulging results in decreased radiance with a local valley in the same range. These changes in radiance are influenced by both temperature and emissivity variations, with the characteristic waveband relating to quartz emissivity changes.
Article
Optics
C. Leone, S. Genna, F. Bertocchi, M. Giordano, A. Martone
Summary: The paper presents an experimental procedure for measuring the emissivity of ultra-thin graphene based films, which shows that the measuring temperature and test methods do not affect the emissivity, while the emissivity decreases as the graphene content increases.
OPTICS AND LASER TECHNOLOGY
(2021)
Article
Chemistry, Multidisciplinary
Guoliang Chen, Haoyang Fu, Yongchun Zou, Shuqi Wang, Yongwang Gao, Tongtong Yue, Jianyun Cao, Yaming Wang, Jun Qiu, Junming Zhao, Jiahu Ouyang, Dechang Jia, Yong Shuai, Yu Zhou
Summary: In this study, a Ca-Cr co-doped Y3NbO7 coating with a lamellar porous structure was fabricated, which exhibits an ultra-low thermal conductivity (<0.7 W m(-1) K-1) and near-unity emissivity (>0.9) across a broad wavelength range of 1-24 μm. The coating shows a record high emissivity to thermal conductivity ratio (>1.3) due to diffusion-mediated thermal conduction feature combined with the lamellar porous structure. The coating also exhibits robust mechanical and thermal stability, with a high bonding strength (18.3 MPa) and comparable thermal expansion coefficient to YSZ.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Thermodynamics
Matheus de Oliveira Moreira, Alexandre M. Abrao, Rafael A. M. Ferreira, Matheus P. Porto
Summary: Authors used thermography to monitor thermal and spatial gradients, and estimate temperature, proposing a more suitable methodology using radiative heat transfer directional-spectral relations to estimate cutting process temperatures during face milling of metals. The experimental results showed that the temperature deviation between different estimation methods could be up to 41%.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2021)
Article
Environmental Sciences
Antoin M. O'Sullivan, Barret L. Kurylyk
Summary: By modifying the surface absorptivity of uncooled TIR sensors, thermal drift can be reduced and accuracy can be improved. The foil-shielded sensor yielded higher temperature accuracy compared to the matte black sensor. Additionally, there were positive correlations between light intensity and air temperature changes and sensor accuracy, with changes in surface absorptivity affecting these relationships.
Article
Engineering, Manufacturing
P. Rebesan, M. Ballan, M. Bonesso, A. Campagnolo, S. Corradetti, R. Dima, C. Gennari, G. A. Longo, S. Mancin, M. Manzolaro, G. Meneghetti, A. Pepato, E. Visconti, M. Vedani
Summary: Molybdenum is highly regarded for high-temperature applications as a refractory material. The study showed that powder bed Additive Manufacturing technology can produce nearly fully dense Mo blocks with careful parameter tuning and material analysis, aiming for continuous and homogeneous melt-pool production. However, differences in thermal conductivity and mechanical properties were observed between AM Mo and conventionally manufactured Mo.
ADDITIVE MANUFACTURING
(2021)
Article
Multidisciplinary Sciences
Feifei Ren, Jinxin Gu, Hang Wei, Gaoping Xu, Jiupeng Zhao, Shuliang Dou, Yao Li
Summary: In this study, four switchable infrared metamaterial absorbers/emitters were proposed using Ag/VO2 disks on the Ag plane with different unit cells. The absorption peaks occurred at around 4 μm after optimization of the structure when VO2 is in insulating state, and disappeared when it became metallic state. The absorbers/emitters show stable performance under different incident angles due to their high rotational symmetric structure, indicating promising applications in sensing technology and adaptive infrared systems.
Article
Chemistry, Analytical
Fu Jiao, Fengjing Cao, Yuan Gao, Feng Shuang, Daming Dong
Summary: Flexible-type signal probes and their detection methods are widely used in biosensors, and temperature-based signal probes represent a new research direction. This study proposes a novel sensing method that uses infrared radiance as the signal probe and implements the conversion of immunoassay using a controlled aluminum plate. Two readout systems, including a scientific grade infrared camera and a smartphone-based thermal camera, are developed for detection. The sensors show excellent quantitative model performances with a low detection limit when detecting biomarkers such as human IgG.
Article
Materials Science, Multidisciplinary
Urmi Devi, Reza Pejman, Zachary J. Phillips, Pengfei Zhang, Soheil Soghrati, Kalyana B. Nakshatrala, Ahmad R. Najafi, Kurt R. Schab, Jason F. Patrick
Summary: This paper discusses the manipulation of composite material properties through precise patterning and microvascular structures, providing new insights for future design optimization and real-world application.
ADVANCED MATERIALS TECHNOLOGIES
(2021)
Article
Energy & Fuels
Silvia Trevisan, Wujun Wang, Bjorn Laumert
Summary: This study investigates the thermal stability and cyclic thermal stability of six inorganic coatings applied on a ceramic substrate. The results show that two of the coatings exhibit excellent performance, while others have degradation issues. The studied coatings have a wide range of thermal emissivity, which may affect the effective thermal conductivity of the packing structure.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2022)
Article
Chemistry, Multidisciplinary
Nikita Nefedkin, Ahmed Mekawy, Jonas Krakofsky, Yongrui Wang, Alexey Belyanin, Mikhail Belkin, Andrea Alu
Summary: Engineered intersubband transitions in multi-quantum well semiconductor heterostructures exhibit high second-order nonlinear susceptibilities in metasurfaces. By optimizing the design, the saturation limits in mid-infrared frequency upconversion in nonlinear metasurfaces are significantly extended. This has important implications for night-vision imaging and compact nonlinear wave mixing systems.
ADVANCED MATERIALS
(2023)
Article
Multidisciplinary Sciences
Jiaxin Li, Ying Li, Pei-Chao Cao, Minghong Qi, Xu Zheng, Yu-Gui Peng, Baowen Li, Xue-Feng Zhu, Andrea Alu, Hongsheng Chen, Cheng-Wei Qiu
Summary: The reciprocity principle governs the symmetry in transmission of electromagnetic and acoustic waves, as well as the diffusion of heat. Recent interest in materials with time-modulated properties has shown efficient breaking of reciprocity for various forms of diffusion. However, time modulation may not be a viable approach to break thermal reciprocity. Our theoretical framework and experimental demonstration highlight the generally preserved nature of thermal reciprocity in dynamic materials.
NATURE COMMUNICATIONS
(2022)
Article
Multidisciplinary Sciences
Xiaoqian Shu, Aodong Li, Guangwei Hu, Jian Wang, Andrea Alu, Lin Chen
Summary: The authors propose a highly efficient and compact chiral mode converter based on encircling exceptional points, enabling chiral mode switching with high transmission efficiency. The proposed scheme offers a promising approach for high-efficiency and highly integrated chiral mode switching in various practical applications.
NATURE COMMUNICATIONS
(2022)
Article
Multidisciplinary Sciences
Qing Zhang, Qingdong Ou, Guangyuan Si, Guangwei Hu, Shaohua Dong, Yang Chen, Jincheng Ni, Chen Zhao, Michael S. Fuhrer, Yuanjie Yang, Andrea Alu, Rainer Hillenbrand, Cheng-Wei Qiu
Summary: Recent research has shown that highly asymmetric and unidirectional phonon polaritons can be excited by directly patterning high-symmetry crystal structures. Structural engineering in high-symmetry vdW materials allows versatile and robust control over the propagation of phonon polaritons, opening up new possibilities for controlling infrared polaritons.
Article
Chemistry, Multidisciplinary
Julian Klein, Zhigang Song, Benjamin Pingault, Florian Dirnberger, Hang Chi, Jonathan B. Curtis, Rami Dana, Rezlind Bushati, Jiamin Quan, Lukas Dekanovsky, Zdenek Sofer, Andrea Alu, Vinod M. Menon, Jagadeesh S. Moodera, Marko Loncar, Prineha Narang, Frances M. Ross
Summary: Atomic-level defects in van der Waals (vdW) materials are essential for quantum technologies and sensing applications. The magnetic semiconductor CrSBr, with a direct gap and rich magnetic phase diagram, exhibits optically active defects that are correlated with the magnetic environment. The narrow defect emission in CrSBr is related to both the bulk magnetic order and an additional defect-induced magnetic order. This study establishes vdW magnets like CrSBr as an exceptional platform for studying defects and creating tailor-made magnetic textures with optical access.
Article
Nanoscience & Nanotechnology
Guangwei Hu, Weiliang Ma, Debo Hu, Jing Wu, Chunqi Zheng, Kaipeng Liu, Xudong Zhang, Xiang Ni, Jianing Chen, Xinliang Zhang, Qing Dai, Joshua D. Caldwell, Alexander Paarmann, Andrea Alu, Peining Li, Cheng-Wei Qiu
Summary: Various optical crystals with opposite permittivity components have been observed and characterized in the mid-infrared regime. These crystals possess hyperbolic polaritons with large-momenta optical modes and wave confinement, making them promising for nanophotonic on-chip technologies. Monoclinic CdWO4 crystals are shown to exhibit symmetry-broken hyperbolic phonon polaritons and offer new opportunities for polaritonic phenomena.
NATURE NANOTECHNOLOGY
(2023)
Article
Nanoscience & Nanotechnology
Andrea Cordaro, Brian Edwards, Vahid Nikkhah, Andrea Alu, Nader Engheta, Albert Polman
Summary: As traditional microelectronic technology reaches its limits in speed and power consumption, there is a strong demand for novel computing strategies. Analogue optical computing has the advantage of processing large amounts of data at high speeds with negligible energy costs. Researchers have recently explored ultrathin optical metasurfaces for real-time image processing, particularly for edge detection. By incorporating feedback, they have also demonstrated that metamaterials can be used to solve complex mathematical problems, although this has been limited to guided-wave systems and large setups. This study presents an ultrathin Si metasurface-based platform for analogue computing, capable of solving Fredholm integral equations of the second kind using free-space visible radiation. The device combines an inverse-designed Si-based metagrating with a semitransparent mirror to perform the required Neumann series and solve the equation in the analogue domain at the speed of light. The use of visible wavelength operation enables a compact, ultrathin device that can be integrated on a chip and has high processing speeds.
NATURE NANOTECHNOLOGY
(2023)
Editorial Material
Materials Science, Multidisciplinary
Andrea Alu
Summary: Optical Materials Express Editor-in-Chief, Andrea Ali, has introduced new topic categories for the Journal, redefining the Journal scope and better reflecting the current state of this dynamic field of research.
OPTICAL MATERIALS EXPRESS
(2023)
Article
Materials Science, Multidisciplinary
Andrew Butler, Christos Argyropoulos
Summary: In this work, the unique properties of a plasmonic Huygens' metasurface composed of active metal-dielectric core-shell nanoparticles are analyzed. The reflection and transmission coefficients of the metasurface are calculated under various levels of gain, demonstrating the existence of reflectionless transmission when an exceptional point is formed. The proposed new active metasurface design, with subwavelength thickness, can be used to realize ultracompact perfect transmission optical filters.
OPTICAL MATERIALS EXPRESS
(2023)
Article
Nanoscience & Nanotechnology
Sander A. . Mann, Heedong Goh, Andrea Alu
Summary: Enabling strong nonlinear optical phenomena requires carefully designed photonic devices to maximize light-matter interactions. Topology optimization has been widely used in optimizing photonic devices due to its efficiency in dealing with large parameter spaces. However, the application of topology optimization in nonlinear effects in dielectric structures is limited.
Article
Nanoscience & Nanotechnology
Nikita Nefedkin, Michele Cotrufo, Andrea Alu
Summary: Nonreciprocity originating from classical interactions among nonlinear scatterers is explored in this work, offering a promising tool for quantum information processing and quantum computing. It is shown that large nonreciprocal responses can be achieved in nonlinear systems by controlling the position and transition frequencies of the atoms, without requiring a nonreciprocal environment. The connection between this effect and the asymmetric population of a slowly decaying dark state is demonstrated.
Article
Physics, Applied
Tianjing Guo, Christos Argyropoulos
Summary: Graphene can support highly confined plasmons and can strongly couple with nanostructures and gratings, leading to new hybrid systems for investigating complex plasmonic phenomena. In this Perspective, the excitation of graphene plasmons and their strong coupling with metallic or dielectric gratings are analyzed, highlighting the flexibility in controlling light-matter interaction. The hybrid graphene-plasmon grating systems offer tunable plasmonic resonances with enhanced field distributions, enabling practical applications such as nonreciprocal devices, plasmonic switches, perfect absorbers, nonlinear structures, photodetectors, and optical sensors.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Optics
Andrew Butler, Christos Argyropoulos
Summary: Nonreciprocal thermal emission is a leading-edge technology that enables control over thermal radiation and has exciting applications in thermal energy harvesting. This work proposes different structures combining a Weyl semimetal thin film with additional layers to achieve nonreciprocal emission over a broad wavelength range and for multiple angles. The designs can be realized through simple deposition fabrication methods and have potential for use in creating broadband nonreciprocal thermal emitters for energy harvesting devices.
JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Luca Stefanini, Shixiong Yin, Davide Ramaccia, Andrea Alu, Alessandro Toscano, Filiberto Bilotti
Summary: This paper investigates the possibility of realizing temporal metamaterials without changing the material properties, but by varying the boundaries to manipulate the effective refractive index and wave impedance perceived by the wave during propagation. The concept of suddenly changing the structural dispersion of a waveguide through varying boundary conditions is demonstrated to induce an effective temporal interface. This approach can also be extended to temporally controlled metasurfaces, enabling easier design and realization of novel devices based on time-varying metamaterials at microwave and optical frequencies.
Article
Optics
Shixiong Yin, Yao-Ting Wang, Andrea Alu
Summary: This work investigates wave scattering at time-interfaces involving chiral media and demonstrates the effect of temporal optical activity. The study shows that a propagating wave can be split into two orthogonal circular polarization waves oscillating at different frequencies upon a chiral time-interface. The analysis also considers the effect of material dispersion and highlights opportunities for the emergence of multiple scattered waves from the time-interface and interference.
