Generalized Kirchhoff law

  title={Generalized Kirchhoff law},
  author={Jean-Jacques Greffet and Patrick Bouchon and Giovanni Brucoli and Emilie Sakat and Franccois Marquier},
  journal={arXiv: Optics},
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, we study the link between thermal emission and absorption by a finite size object which is not isothermal. We define a local absorption rate for a given incident plane wave and we prove that it is equal to the local emissivity rate. Hence, Kirchhoff law can… 

Figures from this paper

Transformational fluctuation electrodynamics: application to thermal radiation illusion.

It is demonstrated that it is possible for objects residing in two spaces, virtual and physical, to have the same thermal radiation signature if the complex permittivities and permeabilities satisfy the standard space transformations.

Large nonreciprocal absorption and emission of radiation in type-I Weyl semimetals with time reversal symmetry breaking

The equality between the spectral, directional emittance and absorptance of an object under local thermal equilibrium is known as Kirchhoff's law of radiation. The breakdown of Kirchhoff's law of

Temperature-dependent and optimized thermal emission by spheres

We investigate the temperature and size dependencies of thermal emission by homogeneous spheres as a function of their dielectric properties. Different power laws obtained in this work show that the

Upper bound for the thermal emission of a hot nanoemitter assisted by a cold nanoantenna

In the last decades, designs of most incandescent sources have been realized by heating the whole device. Here we propose a novel approach consisting in taking advantage of hot nanoemitters that can

Geometric and doping effects on radiative recombination in thin-film near-field energy converters

Modeling radiative recombination is crucial to the analysis of radiative energy converters. In this work, a local radiative recombination coefficient is defined and derived based on fluctuational

Quantitative Assessment of Carrier Density by Cathodoluminescence. I. GaAs Thin Films and Modeling

Doping is a fundamental property of semiconductors and constitutes the basis of modern microelectronic and optoelectronic devices. Their miniaturization requires contactless characterization of

Revisiting the Role of Metallic Antennas to Control Light Emission by Lead Salt Nanocrystal Assemblies

Thin films of lead salt nanocrystals (NCs) offer attractive opportunities as active media for near-infrared optoelectronics but suffer from limiting trade-offs between optical and electrical

Enhanced Heat-Electric Conversion via Photonic-Assisted Radiative Cooling

It is found that the temperature gradient can be increased via the effective radiative cooling process, and the corresponding output current can be enhanced 1.67-fold via the photonic-assisted radiativecool.

Radiation in equilibrium with plasma and plasma effects on cosmic microwave background.

It is shown that, while plasma effects cannot be realistically detected with technology available in the near future, there are a number of quantifiable ways in which plasma affects cosmic microwave background radiation.

Quantitative Assessment of Carrier Density by Cathodoluminescence. II. GaAs Nanowires

Precise control of doping in single nanowires (NWs) is essential for the development of NW-based devices. Here, we investigate a series of MBE-grown GaAs NWs with Be (p-type) and Si (n-type) doping



Universal modal radiation laws for all thermal emitters

Revised versions of laws that avoid these problems and discover additional and unexpected radiation laws that substantially expand the fundamental relations between optical absorption and emission are derived.

Overcoming black body radiation limit in free space: metamaterial superemitter

Here, we demonstrate that the power spectral density of thermal radiation at a specific wavelength produced by a body of finite dimensions set up in free space under a fixed temperature could be made

Direct and Indirect Methods for Calculating Thermal Emission From Layered Structures With Nonuniform Temperatures

The determination of emissivity of layered structures is critical in many applications, such as radiation thermometry, microelectronics, radiative cooling, and energy harvesting. Two different

Electrical modulation of emissivity

We demonstrate that it is possible to modulate the thermal emission through an electrical modulation of the emissivity. The basic idea is to design a device where absorption is due to a resonant

Coherent spontaneous emission of light by thermal sources

The emission of light by a material at temperature T has been shown recently to be coherent in the near field. These properties were attributed to the thermal excitation of surface polaritons. We

Super-Planckian far-zone thermal emission from asymmetric hyperbolic metamaterials

We demonstrate the production of strong directive thermal emissions in the far-field zone of asymmetric hyperbolic metamaterials (AHMs), exceeding that predicted by Planck's limit. Asymmetry is

The chemical potential of radiation

In a thermodynamic treatment electromagnetic radiation of any kind is described. The difference between thermal and non-thermal radiation is accounted for by introducing the chemical potential of

Field theory for generalized bidirectional reflectivity: derivation of Helmholtz’s reciprocity principle and Kirchhoff’s law

A generalized bidirectional distribution function (BRDF) that relates the specific intensity of the scattered light from a semi-infinite medium to the specific intensity of the incident light is