Related papers: True thermal antenna with hyperbolic metamaterials
Whereas thermoelectric performance is normally limited by the figure of merit ZT, transverse thermoelectrics can achieve arbitrarily large temperature differences in a single leg even with inferior ZT by being geometrically tapered. We…
Unidirectional electromagnetic absorption provides a powerful approach for controlling light and heat, yet broadband realization in the infrared spectral region remains experimentally unexplored. Here, we report a non-Hermitian multilayer…
We experimentally demonstrate an infrared broadband absorber for TM polarized light based on an array of nanostrip antennas of several different sizes. The broadband property is due to the collective effect of magnetic responses excited by…
Thermionic converters generate electricity from thermal energy in a power cycle based on vacuum emission of electrons. While thermodynamically efficient, practical implementations are limited by the extreme temperatures required for…
We have developed a heat shield based on a metamaterial engineering approach to shield a region from transient diffusive heat flow. The shield is designed with a multilayered structure to prescribe the appropriate spatial profile for heat…
In this paper we present a novel telescope composed exclusively of thin, flat optical elements, each being a hot-pressed multi-layered structure combining the properties of a lens, its anti-reflection coating and frequency selection or…
In the close vicinity of a hot body, at distances smaller than the thermal wavelength, a high electromagnetic energy density exists due to the presence of evanescent fields radiated by the partial charges in motion around its surface. This…
We derive the energy density associated with an electromagnetic wave passing through a hyperbolic metamaterial (HMM). Both types of HMMs are studied. By considering a dispersive and absorbing HMM as an effective uniaxial crystal, we find…
An important source of innovation in nanophotonics is the idea to scale down known radio wave technologies to the optical regime. One thoroughly investigated example of this approach are metallic nanoantennas which employ plasmonic…
In this work, we introduce a concept to enable dynamic beamforming of terahertz (THz) wavefronts using applied magnetic fields (B). The proposed system exploits the magnetically switchable hyperbolic dispersion of the InSb semiconductor.…
In passive sky-facing radiative cooling, wavelength-selective thermal emitters in the atmospheric transparency window of 8-13 $\mu$m can reach lower temperatures compared to broadband emitters, but broadband emitters always have higher…
Heat flux exchanged between two hot bodies at subwavelength separation distances can exceed the limit predicted by the blackbody theory. However this super-Planckian transfer is restricted to these separation distances. Here we demonstrate…
We report on optical design and applications of hybrid meso-scale devices and materials that combine optical and thermal management functionalities owing to their tailored resonant interaction with light in visible and infrared frequency…
We analyze the use of layered superconductors as anisotropic metamaterials. Layered superconductors can have a negative refraction index in a wide frequency range for arbitrary incident angles. Indeed, low-Tc (s-wave) superconductors allow…
Metal nanoantennas supporting localized surface plasmon resonances have become an indispensable tool in bio(chemical) sensing and nanoscale imaging applications. The high plasmon-enhanced electric field intensity in the visible or near-IR…
Optical travelling wave antennas offer unique opportunities to control and selectively guide light into a specific direction which renders them as excellent candidates for optical communication and sensing. These applications require state…
Graphene is a two-dimensional (2D) material with over 100-fold anisotropy of heat flow between the in-plane and out-of-plane directions. High in-plane thermal conductivity is due to covalent sp2 bonding between carbon atoms, whereas…
We study the properties of an electromagnetically interacting medium in the presence of high concentration of electrons at extremely high temperatures and chemical potentials. We show that the electromagnetic properties of a medium such as…
The thermal emission of refractory plasmonic metamaterial - a titanium nitride 1D grating - is studied at high operating temperature (540 {\deg}C). By choosing a refractory material, we fabricate thermal gratings with high brightness that…
Sound is usually generated in a medium by an electromechanical vibrating structure. The geometrical size and inertia of the structure set the frequency cutoff in the sound-transduction mechanism and, often, different vibrating structures…