Nonthermal Radiation of the Extreme TeV Blazar 1ES 0229+200 from Electromagnetic Cascades on Infrared Photon Field

Extreme TeV blazars (ETBs) are active galactic nuclei with jets presumably pointing towards the observer having their intrinsic (compensated for the effect of γ-ray absorption on extragalactic background light photons) spectral energy distributions (SEDs) peaked at an energy in excess of 1 TeV. These sources typically reveal relatively weak and slow variability as well as higher frequency of the low-energy SED peak compared to other classes of blazars. It proved to be exceedingly hard to incorporate all these peculiar properties of ETBs into the framework of conventional γ-ray emission models. ETB physics have recently attracted great attention in the astrophysical community, underlying the importance of the development of self-consistent ETB emission model(s). We propose a new scenario for the formation of X-ray and γ-ray spectra of ETBs assuming that electromagnetic cascades develop in the infrared photon field surrounding the central blazar engine. This scenario does not invoke compact fast-moving sources of radiation (so-called “blobs”), in agreement with the apparent absence of fast and strong variability of ETBs. For the case of the extreme TeV blazar 1ES 0229+200 we propose a specific emission model in the framework of the considered scenario. We demonstrate that this model allows to obtain a good fit to the measured SED of 1ES 0229+200.

The Classical and Quantum Photon Field for Non-compact Manifolds with Boundary and in Possibly Inhomogeneous Media

In this article I give a rigorous construction of the classical and quantum photon field on non-compact manifolds with boundary and in possibly inhomogeneous media. Such a construction is complicated by zero-modes that appear in the presence of non-trivial topology of the manifold or the boundary. An important special case is $${\mathbb {R}}^3$$ R 3 with obstacles. In this case the zero modes have a direct interpretation in terms of the topology of the obstacle. I give a formula for the renormalised stress energy tensor in terms of an integral kernel of an operator defined by spectral calculus of the Laplace Beltrami operator on differential forms with relative boundary conditions.

Photon-Assisted Seebeck Effect in a Quantum Dot Coupled to Majorana Zero Modes

The Seebeck effect is investigated within the framework of a non-equilibrium Green's function technique in a quantum dot (QD) sandwiched between the left and right leads held at different temperatures. We consider that the QD is shelled by a photon field and is side-coupled to a topological superconductor nanowire hosting Majorana zero modes (MZMs). It is found that the thermopower (Seebeck coefficient) can be obviously enhanced by weak QD-MZMs coupling at low temperatures, in addition to its sign reversion that may be used for detecting the existence of MZMs. In the presence of a photon field, the thermopower can be further enhanced due to decreased electrical conductance when electrons' transport probability through each channel is reduced by photon-assisted tunneling (PAT). The hybridization between the MZMs will also induce sign reversion of the thermopower in the absence of a photon field, whereas it has less impact on the thermopower when the QD is shelled by the photon field.

Light dark photon dark matter from inflation

We discuss the possibility of producing a light dark photon dark matter through a coupling between the dark photon field and the inflaton. The dark photon with a large wavelength is efficiently produced due to the inflaton motion during inflation and becomes non-relativistic before the time of matter-radiation equality. We compute the amount of production analytically. The correct relic abundance is realized with a dark photon mass extending down to 10−21 eV.

Ring-Polymer Quantization of Photon Field in Polariton Chemistry

We use the ring-polymer (RP) representation to quantize the radiation field inside an optical cavity to investigate polariton quantum dynamics. Using a charge transfer model coupled to an optical cavity, we demonstrate that the RP quantization of the photon field provides accurate rate constants of the polariton mediated electron transfer (PMET) reaction compared to the Fermi's Golden rule. Because RP quantization uses extended phase space to describe the photon field, it significantly reduces the computational costs compared to the commonly used Fock states description of the radiation field. Compared to the other quasi-classical descriptions of the photon field, such as the classical Wigner model, the RP representation provides a much more accurate description of the polaritonic quantum dynamics, because it properly preserves the quantum distribution of the photonic DOF throughout the quantum dynamics propagation of the molecule-cavity hybrid system, whereas the classical Wigner model fails to do so. This work demonstrates the possibility of using the ring-polymer description to treat the quantized radiation field in polariton chemistry, offering an accurate and efficient approach for future investigations in cavity quantum electrodynamics.

Ring-Polymer Quantization of Photon Field in Polariton Chemistry

We use the ring-polymer (RP) representation to quantize the radiation field inside an optical cavity to investigate polariton quantum dynamics. Using a charge transfer model coupled to an optical cavity, we demonstrate that the RP quantization of the photon field provides accurate rate constants of the polariton mediated electron transfer (PMET) reaction compared to the Fermi's Golden rule. Because RP quantization uses extended phase space to describe the photon field, it significantly reduces the computational costs compared to the commonly used Fock states description of the radiation field. Compared to the other quasi-classical descriptions of the photon field, such as the classical Wigner model, the RP representation provides a much more accurate description of the polaritonic quantum dynamics, because it properly preserves the quantum distribution of the photonic DOF throughout the quantum dynamics propagation of the molecule-cavity hybrid system, whereas the classical Wigner model fails to do so. This work demonstrates the possibility of using the ring-polymer description to treat the quantized radiation field in polariton chemistry, offering an accurate and efficient approach for future investigations in cavity quantum electrodynamics.