Ref HAL: hal-01421877_v1
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Planar structures cannot emit more heat by radiation than predicted by Stefan- Boltzmann’s law. However, when two reservoirs are connected by an intermediate slab which is placed in their near-field one can in principle observe a super-Planckian heat flux at separation distances larger than the thermal wavelength, if the evanescent contributions can be perfectly guided through the intermediate slab. In this case study we discuss in particular how the thermal near-field of the surface modes of two SiC reservoirs can be guided through an ideal dielectric, a perfect lens and a hyperbolic waveguide. A detailed study of the parameters needed in order to have a long-range guiding of thermal radiation shows which properties are ideally needed in order to observe a super-Planckian heat flux. In particular hyperbolic materials which are known for their large penetration depth of radiative heat fluxes are promising materials. This result opens the way to long distance transport of near-field thermal energy.

Ref HAL: hal-01421873_v1
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We show that the electromagnetic forces generated by the excitations of a mode in graphene-based optomechanical systems are highly tunable by varying the graphene chemical potential, and orders of magnitude stronger than usual non-graphene-based devices, in both attractive and repulsive regimes. We analyze coupled waveguides made of two parallel graphene sheets, either suspended or supported by dielectric slabs, and study the interplay between the light-induced force and the Casimir-Lifshitz interaction. These findings pave the way to advanced possibilities of control and fast modulation for optomechanical devices and sensors at the nano- and microscales.

Ref HAL: hal-01625151_v1
DOI: 10.1016/bs.aiep.2016.08.002
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The purpose of this chapter is to present a unified theory for the numerical implementation of modal methods for the analysis of electromagnetic phenomena with specific boundary conditions. All the fundamental concepts that form the basis of our study will be detailed. In plasmonics and photonics in general, solving Maxwell equations involving irregular functions is common. For example, when the relative permittivity is a piecewise constant function describing a dielectric–metal interface, the eigenmodes of the propagation equation are solutions of Maxwell's equations subject to specific boundary conditions at the interfaces between homogenous media. Prior knowledge about the eigenmodes allows one to define more appropriate expansion functions, and the rate of convergence of the numerical scheme will depend on the choice of these functions. In this chapter, we present and explain, a unified numerical formalism that allows one to build, from a set of subsectional functions defined on a set of subintervals, expansion functions defined on a global domain by enforcing certain stresses deduced from electromagnetic field properties. Then numerical modal analysis of a plasmonic device, such as a ring resonator, is presented as an example of an application.

Ref HAL: hal-01420542_v1
DOI: 10.1103/PhysRevE.94.043310
WoS: 000386386300012
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1 Citation
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We present a numerical approach for the solution of the dissipative Gross-Pitaevskii equation coupled to the reservoir equation governing the exciton-polaritons Bose-Einstein condensation. It is based on the finite difference method applied to space variables and on the fourth order Range-Kutta algorithm applied to the time variable. Nu- merical tests illustrate the stability and accuracy of the proposed scheme. Then results on the behavior of the con- densate under large Gaussian pumping and around the threshold are presented. We determine the threshold through the particular behavior of the self-energy and characterize it by tracking the establishment time of the steady state.

Ref HAL: hal-01419660_v1
Ref Arxiv: 1611.09856
Ref. & Cit.: NASA ADS
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We present the latest developments to the CheckMATE program that allows models of new physics to be easily tested against the recent LHC data. To achieve this goal, the core of CheckMATE now contains over 60 LHC analyses of which 12 are from the 13 TeV run. The main new feature is that CheckMATE 2 now integrates the Monte Carlo event generation via Madgraph and Pythia 8. This allows users to go directly from a SLHA file or UFO model to the result of whether a model is allowed or not. In addition, the integration of the event generation leads to a significant increase in the speed of the program. Many other improvements have also been made, including the possibility to now combine signal regions to give a total likelihood for a model.

Commentaires: 53 pages, 6 figures

Ref HAL: hal-01419370_v1
Ref Arxiv: 1509.07589
DOI: 10.1063/1.4962920
WoS: WOS:000385564900031
Ref. & Cit.: NASA ADS
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2 Citations
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Using the nested coordinate Bethe ansatz, we study 33-vertex models, where only one global charge with degenerate eigenvalues exists and each site possesses three internal degrees of freedom. In the context of Markovian processes, they correspond to diffusing particles with two possible internal states which may be exchanged during the diffusion (transmutation). The first step of the nested coordinate Bethe ansatz is performed providing the eigenvalues in terms of rapidities. We give the constraints ensuring the consistency of the computations. These rapidities also satisfy Bethe equations involving $4\times 4$ R-matrices, solutions of the Yang--Baxter equation which implies new constraints on the models. We solve them allowing us to list all the solvable 33-vertex models.

Commentaires: 14 pages; title changed according to referee request; an appendix added to describe explicitely the Hamiltonian

Ref HAL: hal-01419364_v1
Ref Arxiv: 1603.06796
DOI: 10.1103/PhysRevE.94.032102
WoS: WOS:000383052100002
Ref. & Cit.: NASA ADS
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13 Citations
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We study a one-parameter generalization of the symmetric simple exclusion process on a one-dimensional lattice. In addition to the usual dynamics (where particles can hop with equal rates to the left or to the right with an exclusion constraint), annihilation and creation of pairs can occur. The system is driven out of equilibrium by two reservoirs at the boundaries. In this setting the model is still integrable: it is related to the open XXZ spin chain through a gauge transformation. This allows us to compute the full spectrum of the Markov matrix using Bethe equations. We also show that the stationary state can be expressed in a matrix product form permitting to compute the multipoints correlation functions as well as the mean value of the lattice and the creation-annihilation currents. Finally, the variance of the lattice current is computed for a finite-size system. In the thermodynamic limit, it matches the value obtained from the associated macroscopic fluctuation theory.