Related papers: Cool windows: simultaneously engineering high visi…
Engineered optical absorbers are of substantial interest for applications ranging from stray light reduction to energy conversion. We demonstrate a large-area (centimeter-scale) metamaterial that features near-unity frequency-selective…
Dynamic radiative thermal control is crucial for normal operation and energy saving of spacecraft that copes with changing thermal environment involving heat dissipation to cold deep space, external heating from the Sun and nearby planet,…
We experimentally demonstrate imaging in the longwave-infrared (LWIR) spectral band (8um to 12um) using a single polymer flat lens based upon multi-level diffractive optics. The device thickness is only 10{\mu}m, and chromatic aberrations…
Dielectric metasurfaces require high refractive index contrast materials for optimum performance. This requirement imposes a severe restraint; devices have either been demonstrated at wavelengths of 700nm and above using high-index…
Thermionic energy conversion (TEC) using nano materials is an emerging field of research. Graphene can stand high temperature as high as 4600 K in vacuum. Its work function can be engineered from its high value (for monolayer/bilayer) 4.6…
A thin conducting sheet - graphene, for example - transmits, absorbs, and reflects radiation. A sheet that is very thin, even vanishingly so, can still produce 50% absorption at normal incidence if it has conductivity corresponding to half…
Measuring the temperature structure of the solar atmosphere is critical to understanding how it is heated to high temperatures. Unfortunately, the temperature of the upper atmosphere cannot be observed directly, but must be inferred from…
The spectral response and directional scattering of semiconductor-oxide core-shell spherical microparticles embedded in an insulating medium at low volume fraction are computed using Mie Theory and Multiscale Modelling methods. The surface…
An antireflective coating presenting a continuous refractive index gradient is theoretically better than its discrete counterpart because it can give rise to a perfect broadband transparency. This kind of surface treatment can be obtained…
A two-dimensional model is proposed for energy efficiency assessment through the simulation of heat transfer in building envelopes, considering the influence of the surrounding environment. The model is based on the \DF ~approach that…
Extended from its electromagnetic counterpart, transformation thermodynamics applied to thermal conduction equations can map a virtual geometry into a physical thermal medium, realizing the manipulation of heat flux with almost arbitrarily…
This work experimentally studies silicon-cored tungsten nanowire selective metamaterial absorber to enhance solar-thermal energy harvesting, simply fabricated by conformally coating a thin tungsten layer onto a commercial silicon nanowire…
We propose a sub-Doppler laser cooling mechanism that takes advantage of the unique spectral features and extreme dispersion generated by the phenomenon of electromagnetically induced transparency (EIT). EIT is a destructive quantum…
Passive daytime radiative cooling (PDRC) provides an energy-free approach to suppress surface temperatures by reflecting solar irradiation while emitting thermal radiation through the mid-infrared atmospheric window. Despite rapid progress…
While advancing a physics-based comprehensive photodetector-simulation model, we propose a novel device design of the mid-wavelength infrared nBn photodetectors by exploiting the inherit flexibility of the $InAs_{1-x}Sb_{x}$ ternary alloy…
In the present work, the effects of diffuse and collimated radiation on the symmetrical cooling case of natural convection in a two-dimensional cavity heated from the bottom have been investigated, numerically. The cavity is convectively…
Lack of materials which are thermoelectrically efficient and economically attractive is a challenge in thermoelectricity. Silicon could be a good thermoelectric material offering CMOS compatibility, harmlessness and cost reduction but it…
As part of our efforts to complete the software CODYRUN validation, we chose as test building a block of flats constructed in Reunion Island, which has a humid tropical climate. The sensitivity analysis allowed us to study the effects of…
We report a high-performance thermochromic VO2-based coating prepared by using a three-step process, consisting of magnetron sputter depositions of SiO2 films and V-W films and their postannealing, on standard glass at a low substrate…
We show that engineered diffraction gratings can considerably simplify the design and performance of acoustic devices. Acoustic reflecting gratings based on rectangular cavities drilled on an acoustically rigid surface are designed in such…