相关论文: Controlling The Contrast Between Absorptivity and …
The Kirchhoff`s law of thermal radiation stating the equivalence of emissivity and absorptivity at the same wavelength, angle, and polarization, has completely constrained emission and absorption processes. Achieving strong nonreciprocal…
Kirchhoff's law of thermal radiation, which dictates that the emissivity of a surface equals its absorptivity under thermal equilibrium, which dictates that the emissivity of a surface equals its absorptivity under thermal equilibrium,…
Thermal radiation is strictly governed by Kirchhoff s law to reach thermal equilibrium. The violation of Kirchhoff s law decouples nonreciprocally the equity between absorptivity and emissivity, enabling exotic thermal engineering…
Thermal emission can be conveniently described using Kirchhoff law which states that the emissivity is equal to the absorptivity for isothermal bodies. For a finite size system, absorptivity is replaced by an absorption cross section. Here,…
Kirchhoff's law of thermal radiation imposes a constraint on photon-based energy harvesting processes since part of the incident energy flux is inevitably emitted back to the source. By breaking the reciprocity of the system, it is possible…
Spectral/angular emissivity $e$ and absorptivity ${\alpha}$ of an object are widely believed to be identical by Kirchhoff's law of thermal radiation in reciprocal systems, but this introduces an intrinsic and inevitable energy loss for…
To violate Kirchhoff s law is very important in the areas of thermal radiation. However, due to the weak nonreciprocity in natural materials, it is necessary to engineer novel structures to break the balance between emission and absorption.…
Coherent thermal emission for a given polarization has been observed in many metamaterials with micro/nanostructures. A complete description of the thermal emission requires the full characterization of the spectral angular emissivity for…
Kirchhoff s law is one of the most fundamental law in thermal radiation. The violation of traditional Kirchhoff s law provides opportunities for higher energy conversion efficiency. Various micro-structures have been proposed to realize…
Nonreciprocal thermal emitters that break the conventional Kirchhoff's law allow independent control of emissivity and absorptivity and promise exciting new functionalities in controlling heat flow for thermal and energy applications. In…
Planck's law of thermal radiation depends on the temperature, $T$, and the emissivity, $\epsilon$, of a body, where emissivity is the coupling of heat to radiation that depends on both phonon-electron nonradiative interactions and…
Radiative cooling has showcased great potential for passive refrigeration without extra energy consumption, while its cooling power and efficiency is confined by Kirchhoff's law, that is, the emissivity is equal to the absorptivity. The…
Nonreciprocal elements are a vital building block of electrical and optical systems. In the infrared regime, there is a particular interest in structures that break reciprocity because their thermal absorptive (and emissive) properties…
Kirchhoff's law provides a relation between the incident fields a structure can absorb and those it thermally emits. It is generally formulated as a relation between the angle-dependent emissivity and absorptivity of a structure. In this…
Breaking Kirchhoff's law of thermal radiation yields new opportunities in one-way radiative thermal transport and circuitry. We investigate its consequences in the far-field regime in cylindrical cavities, by employing a specular…
Planck's law of thermal radiation depends only on the temperature T and emissivity $\varepsilon$. It is one of the most fundamental discoveries about light-matter interaction that led to the development of quantum physics. Another basic…
Reciprocity, the principle that a system response is identical in the forward path compared to the backward path, is a fundamental concept across physics, from electrical circuits and optics to acoustics and heat conduction. Nonreciprocity…
Nonreciprocal thermal emitters that break Kirchhoff's law of thermal radiation promise exciting applications for thermal and energy applications. The design of the bandwidth and angular range of the nonreciprocal effect, which directly…
We study a number of issues related to the emission and absorption radiation by non-relativistic electrons within the framework of a Lorentz-breaking electrodynamics in (3+1) dimensions. Our main results concern how Planck-like spectrum law…
In a hybrid thermal-nonthermal plasma, we find that the dominant emission and absorption mechanisms are synchrotron by nonthermal electrons and bremsstrahlung by thermal electrons. These two processes significantly change the spectrum from…