Results 51 to 60 of about 1,389 (159)

The Benjamin–Ono Equation in the Zero‐Dispersion Limit for Rational Initial Data: Generation of Dispersive Shock Waves

Communications on Pure and Applied Mathematics, EarlyView.
ABSTRACT The leading‐order asymptotic behavior of the solution of the Cauchy initial‐value problem for the Benjamin–Ono equation in L2(R)$L^2(\mathbb {R})$ is obtained explicitly for generic rational initial data u0$u_0$. An explicit asymptotic wave profile uZD(t,x;ε)$u^\mathrm{ZD}(t,x;\epsilon)$ is given, in terms of the branches of the multivalued ...
Elliot Blackstone, Louise Gassot, Patrick Gérard, Peter D. Miller   +3 more
wiley   +1 more source

Front Propagation Through a Perforated Wall

Communications on Pure and Applied Mathematics, EarlyView.
ABSTRACT We consider a bistable reaction– diffusion equation ut=Δu+f(u)$u_t=\Delta u +f(u)$ on RN${\mathbb {R}}^N$ in the presence of an obstacle K$K$, which is a wall of infinite span with many holes. More precisely, K$K$ is a closed subset of RN${\mathbb {R}}^N$ with smooth boundary such that its projection onto the x1$x_1$‐axis is bounded and that ...
Henri Berestycki, François Hamel, Hiroshi Matano   +2 more
wiley   +1 more source

Edge Fluid Turbulence Simulations of Stellarators With GRILLIX

Contributions to Plasma Physics, EarlyView.
ABSTRACT The edge fluid turbulence code GRILLIX has recently been extended from axisymmetric tokamak geometries to support 3D stellarator configurations. Following successful proof‐of‐principle simulations published in Stegmeir et al., we present here a comprehensive simulation of the Wendelstein 7‐AS stellarator.
Andreas Stegmeir, Christoph Pitzal, Barnabas Csillag, Miguel Madeira, Marion Finkbeiner   +4 more
wiley   +1 more source

Measurement of intensity and polarization beatings in the interference of independent optical fields

Physical Review Research, 2020
We experimentally study the intensity and polarization beatings of interfering independent optical fields. Using the tools of intensity interferometry, we measure the beating harmonicity time and the degree of randomness of the polarization beating for ...
Andriy Shevchenko, Tero Setälä
doaj   +1 more source

Effect of Magnetic Islands on Neoclassical Heat Diffusivity in a Global Tokamak Simulation

Contributions to Plasma Physics, EarlyView.
ABSTRACT Resonant magnetic perturbations (RMPs) alter magnetic field topology via island formation and can modify core transport in toroidal fusion devices. Using the global gyrokinetic particle‐in‐cell code XGC‐S, originally developed for stellarator geometries, we quantify how island topology affects neoclassical heat transport in a circular tokamak ...
Joseph X. Li, Toseo Moritaka, Ryutaro Kanno, Gakushi Kawamura, Robert Hager, C.‐S. Chang   +5 more
wiley   +1 more source

Optical Skyrmions with Tunable or Reconfigurable Topology Using Spin‐Decoupled Metaoptics

Laser &Photonics Reviews, EarlyView.
The work introduces advanced optical elements capable of generating and dynamically reconfiguring complex light patterns known as optical skyrmions. By precisely shaping light polarization at the nanoscale, a single engineered metasurface can generate and manipulate robust and tunable polarization textures in an efficient and scalable way.
Andrea Vogliardi, Daniele Bonaldo, Simone Dal Zilio, Vittorio Apolloni, Filippo Romanato, Gianluca Ruffato   +5 more
wiley   +1 more source

Multimode Phonon Lasing via Self‐Induced Optical Coherent Pumping

Laser &Photonics Reviews, EarlyView.
A silicon optomechanical nanobeam generates self‐sustained phonon lasing in multiple competing mechanical modes via self‐pulsing, an intrinsic optical modulation arising from cavity nonlinearity. This self‐organized mechanism enables robust multi‐frequency operation spanning periodic, quasi‐periodic, and chaotic regimes without external modulation. The
David Alonso Tomás, Carlos Mas Arabí, Carles Milián, Néstor E. Capuj, Alejandro Martínez, Daniel Navarro Urrios   +5 more
wiley   +1 more source

Zwanziger’s pairwise little group on the celestial sphere

Journal of High Energy Physics, 2021
We generalize Zwanziger’s pairwise little group to include a boost subgroup. We do so by working in the celestial sphere representation of scattering amplitudes. We propose that due to late time soft photon and graviton exchanges, matter particles in the
Luke Lippstreu
doaj   +1 more source

Near‐Infrared Polarimetric Imaging With Nonlinear Flat‐Optics

Laser &Photonics Reviews, EarlyView.
ABSTRACT A compact and broadband polarimetric imaging platform is presented, based on second‐harmonic generation (SHG) in nonlinear flat‐optics. The system employs periodic all‐dielectric AlGaAs gratings to induce polarization‐dependent SH emission, enabling pixel by pixel direct retrieval of the full Stokes vector from an input intensity distribution ...
Evgenii Menshikov, Marco A. López Sánchez, Paolo Franceschini, Andrea Tognazzi, Domenico de Ceglia, Kristina Frizyuk, Costantino De Angelis   +6 more
wiley   +1 more source

L3 Dynamics and Poincaré Maps in the Restricted Full Three Body Problem

Open Astronomy, 2012
Poincaré maps are a basic dynamical systems tool yielding information about the geometric structure of the phase space of the system. Poincaré maps are however time consuming to compute.
Pihajoki Pauli, Herrera-Sucarrat Elisabet, Palmer Phil, Roberts Mark   +3 more
doaj   +1 more source