相关论文: Non-Planck thermal emission from two-level media
The concept of temperature is one of the key ideas in describing the thermodynamical properties of a physical system. In classical statistical mechanics of ideal gases, the notion of temperature can be described in two different ways, the…
Here we show that within classical physics, the Planck blackbody spectrum can be derived directly from the structure of relativistic spacetime. In noninertial frames, thermal radiation at positive temperature is connected directly to…
Due to its ubiquitous presence, turbulence is often invoked to explain the origin of nonthermal particles in astrophysical sources of high-energy emission. With particle-in-cell simulations, we study decaying turbulence in…
We present a very simple model of a spontaneous emission from a two-level atom, interacting with a field of a finite number of states. Such a process is often said to occur because of the large number of equally-probable states of…
It is predicted that oscillations of temperature during propagation of third sound in a thin superfluid film cause appearance of an alternating electric field in the surrounding space (a peculiar non-stationary thermoelectric effect). The…
Very recently it has been predicted that the far-field radiative heat transfer between two macroscopic systems can largely overcome the limit set by Planck's law if one of their dimensions becomes much smaller than the thermal wavelength…
Exposing a solution to a temperature gradient can lead to the accumulation of particles on either the cold or warm side. This phenomenon, known as thermophoresis, has been discovered more than a century ago, and yet its microscopic origin…
Directional and spectral control of thermal emission is essential for applications in energy conversion, imaging, and sensing. Existing planar, lithography-free epsilon-near-zero (ENZ) films only support transverse-magnetic (TM) control of…
The altered spontaneous emission of an emitter near an arbitrary body can be elucidated using an energy balance of the electromagnetic field. From a classical point of view it is trivial to show that the field scattered back from any body…
The dissipation of turbulent magnetic fields is an appealing scenario to explain the origin of non-thermal particles in high-energy astrophysical sources. However, it has been suggested that the particle distribution may effectively…
We study the thermalization of excitations generated by spontaneous emission events for cold bosons in an optical lattice. Computing the dynamics described by the many-body master equation, we characterize equilibration timescales in…
Controlling the directionality of emitted far-field thermal radiation is a fundamental challenge in contemporary photonics and materials research. While photonic strategies have enabled angular selectivity of thermal emission over narrow…
Research in spintronics often involves generation of heat in nanoscale magnetic systems. This heat generation can be intentional, as when studying effects created by an external applied temperature difference, or unintentional, coming as a…
We develop fluctuational electrodynamics for media with nonlinear optical response in and out of thermal equilibrium. Starting from the stochastic nonlinear Helmholtz equation and using the fluctuation dissipation theorem, we obtain…
We study, in the framework of the Landauer theory, the thermal emission in far-field regime, of arbitrary indefinite planar media and finite size systems. We prove that the flux radiated by the former is bounded by the blackbody emission…
Based on concepts from quantum thermodynamics the two-level system coupled to a single electromagnetic mode is analyzed. Focusing on the case of detuning, where the mode frequency does not match the transition frequency, effective energies…
Nanophotonic engineering of light-matter interaction at subwavelength scale allows thermal radiation that is fundamentally different from that of traditional thermal emitters and provides exciting opportunities for various thermal-photonic…
We study the thermalization and the Bose-Einstein condensation of a paraxial, spectrally narrow beam of quantum light propagating in a lossless bulk Kerr medium. The spatiotemporal evolution of the quantum optical field is ruled by a…
Thermalization is the dynamical process by which a many-body system evolves toward a thermal equilibrium state that maximizes its entropy. In certain cases, however, the establishment of thermal equilibrium is significantly slowed down and…
The theory of optical thermodynamics provides a comprehensive framework that enables a self-consistent description of the intricate dynamics of nonlinear multimoded photonic systems. This theory, among others, predicts a pressure-like…