Ref HAL: hal-04723775_v1
Ref Arxiv: 2403.14322
DOI: 10.1103/PhysRevB.110.115407
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Plasmons and polar phonons are elementary electrodynamic excitations of matter. In 2d and at long wavelengths, they couple to light and act as the system polaritons. They also dictate the scattering of charged carriers. Van der Waals heterostructures offer the opportunity to couple excitations from different layers via long-range Coulomb interactions, modifying both their dispersion and their scattering of electrons. Even when the excitations do not couple, they are still influenced by the screening from all layers, leading to complex dynamical interactions between electrons, plasmons and polar phonons. We develop an efficient ab initio model to solve the dynamical electric response of Van der Waals heterostructures, accompanied by a formalism to extract relevant spectroscopic and transport quantities. Notably, we obtain scattering rates for electrons of the heterostructure coupling remotely with electrodynamic excitations. We apply those developments to BN-capped graphene, in which polar phonons from BN couple to plasmons in graphene. We study the nature of the coupled excitations, their dispersion and their coupling to graphene's electrons. Regimes driven by either phonons or plasmons are identified, as well as a truly hybrid regime corresponding to the plasmon-phonon-polariton at long wavelengths. Those are studied as a function of the graphene's Fermi level and the number of BN layers. In contrast with standard descriptions in terms of surface-optical phonons, we find that the electron-phonon interaction stems from several different modes. Moreover, the dynamical screening of the coupling between BN's LO phonons and graphene's electrons crosses over from inefficient to metal-like depending on the relative value of the phonons' frequency and the energetic onset of interband transitions. While the coupling is significant in general, the associated scattering of graphene's carriers is found to be negligible in the context of electronic transport.

Ref HAL: hal-04961844_v1
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Ref HAL: hal-04752250_v1
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This work is a review of our recent analytical advances of the evolution of surface water solitary waves in Miles and Jeffreys' theories of wind wave interaction in water of finite depth. Although many works have been conducted based on Miles and Jeffreys' approach, only a few studies have been carried out on finite depth. The present review is divided into two major parts. The first corresponds to the surface water waves in a linear regime and its nonlinear extensions. In this part, Miles' theory of wave amplification by wind is extended to the case of finite depth. The dispersion relation provides a wave growth rate depending on depth. A dimensionless water depth parameter, depending on the depth and a characteristic wind speed, induces a

Ref HAL: hal-04945892_v1
DOI: 10.48550/arXiv.2406.16569
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In this article we present a comprehensive study of the totally asymmetric simple exclusion process with pausing particles (pTASEP), a model initially introduced to describe RNAP dynamics during transcription. We extend previous mean-field approaches and demonstrate that the pTASEP is equivalent to the exclusion process with dynamical defects (ddTASEP), thus broadening the scope of our investigation to a larger class of problems related to transcription and translation. We extend the mean-field theory to the open boundary case, revealing the system's phase diagram and critical values of entry and exit rates. However, we identify a significant discrepancy between theory and simulations in a region of the parameter space, indicating severe finite-size effects. To address this, we develop a single-cluster approximation that captures the relationship between current and lattice size, providing a more accurate representation of the system's dynamics. Finally, we extend our approach to open boundary conditions, demonstrating its applicability in different scenarios. Our findings underscore the importance of considering finite-size effects, often overlooked in the literature, when modelling biological processes such as transcription and translation.

Ref HAL: hal-04891856_v1
Ref Arxiv: 2412.09473
Ref INSPIRE: 2858867
DOI: 10.22323/1.473.0042
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A future multi-TeV muon collider would provide an important probe for Majorana neutrinos. A muon collider with a collision energy of $\sim$30 TeV would be sensitive to $\nu_e-\nu_\mu$ transition dipole moments of the order of $\sim 10^{-12}\mu_B$ and would be thus competitive with the latest astrophysical observation and laboratory experiments. Contrary to the latter, the muon collider would have the unique advantage of a direct and clean identification of lepton number and flavour violation. This would establish the Majorana nature of the neutrino and would provide crucial complementary information on the neutrino properties in the event of a (near) future observation at low-energy experiments. Additionally, a muon collider would improve by orders of magnitude the direct bounds on the Majorana neutrino mass matrix entries $m_{e\mu}$ and $m_{\mu\mu}$.

Ref HAL: hal-04885111_v1
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2D materials have shown fascinating fundamental physics as well as exciting technological prospects, from transistors to integrated optoelectronics. Many applications rely on the ability of the 2D material to conduct electrons efficiently. At room temperature, this is mostly limited by the scattering of electrons by phonons. A clear understanding of the electronic transport mechanisms, along with predictive ab initio simulations, are then key to design performant and energy-efficient devices. In this framework, 2D materials present 3 major peculiarities: their reduced dimensionality, the ability to taylor their properties by combining different layers in a van der Waals heterostructure, and the ubiquitous usage of electrostatic doping. The latter refers to the field-effect transistor configuration, in which a gate is used to induce charges in the 2D material and change its Fermi level.We will explore the consequences of those 3 peculiarities on electron-phonon interactions and the scattering mechanisms. We will see how to compute the macroscopic quantities characterising the transport of electrons through the material, and discuss the performances of various layers taken from a database of exfoliable 2D materials build with high-throughput ab initio workflows.

Ref HAL: hal-04883448_v1
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The cooperative binding of molecular agents onto a substrate is pervasive in living systems, particularly stochastic processes inside cells. When the number of binding sites is small enough, we can rely on a fluctuation analysis of the number of substrate-bound units, an experimentally accessible quantity, to study whether a system shows cooperativity. First, we present a general-purpose grand canonical Hamiltonian description of a small one-dimensional (1D) lattice gas with either nearest-neighbor or long-range interactions as prototypical examples of cooperativity-influenced adsorption processes. We propose 1) a criterion to determine whether a given adsorption system exhibits cooperative or anti-cooperative behavior and 2) a method to quantify the amplitude of the ligand-ligand interaction potential. Second, we compare the theoretical predictions of our model to bead assay measurements of the bacterial flagellar motors (BFM) of *E. coli*. In this way, we find evidence that cooperativity controls the mechano-sensitive dynamical assembly of the torque-generating units, the so-called stator units, onto the BFM. Finally, we estimate the stator-stator interaction potential and attempt to quantify the *adaptability* of the BFM.References:[1] https://arxiv.org/abs/2307.00636[2]: https://www.biorxiv.org/content/10.1101/2021.07.05.451114v1