Publications associées à Hamiltonian optics

How Lagrangian States Evolve Into Random Waves

In this paper, we consider a compact connected manifold (X, g) of negative curvature, and a family of semi-classical Lagrangian states f(h)(x) = a(x)e(i phi(x)/h) on X. For a wide family of phases phi, we show that f(h), when evolved by the semi-classical ...

ECOLE POLYTECHNIQUE2022

Mitsuba 2: A Retargetable Forward and Inverse Renderer

Wenzel Alban Jakob, Tizian Lucien Zeltner, Delio Aleardo Vicini, Merlin Eléazar Nimier-David

Modern rendering systems are confronted with a dauntingly large and growing set of requirements: in their pursuit of realism, physically based techniques must increasingly account for intricate properties of light, such as its spectral composition or polar ...

ASSOC COMPUTING MACHINERY2019

Near-field characterization of Bloch surface waves based 2D optical components

Richa Dubey

Bloch surface waves (BSWs) are surface electromagnetic modes that propagate at the interface between a multilayer substrate and a homogeneous external medium. The optical field of the surface mode is confined near the surface of the multilayer. This vertic ...

EPFL2017

Transition of optical regime in miniaturized optical systems: light interactions beyond the refraction limit

Hans Peter Herzig, Toralf Scharf, Myun Sik Kim

We investigate the transition of optical regimes of miniaturized optical systems using two canonical examples, where the refraction of light limits the system performance. A ball-lens and a solid immersion lens (SIL) are considered, whose refractive respon ...

Spie-Int Soc Optical Engineering2016

From Compact Semi-Toric Systems To Hamiltonian S-1-Spaces

Silvia Sabatini

We show how any labeled convex polygon associated to a compact semi-toric system, as de fined by V (u) over tilde Ngoc, determines Karshon's labeled directed graph which classifies the underlying Hamiltonian S-1-space up to isomorphism. Then we characteriz ...

Amer Inst Mathematical Sciences2015

Two-phase free-surface fluid dynamics on moving domains

Thomas Zimmermann, Matthias Preisig

We develop in this paper a model for the numerical simulation of free surface debris- and mudflows, described as a mixture of two viscous phases A Lagrangian approach with finite element approximation and regular remeshing is adopted in this paper. The pro ...

2010

On A Class Of Mean Field Solutions Of The Monge Problem For Perfect And Self-Interacting Systems

Philippe Choquard

The Monge problem (Monge 1781; Taton 1951), as reformulated by Kantorovich (2006a, 2006b) is that of the transportation at a minimum "cost" of a given mass distribution from an initial to a final position during a given time interval. It is an optimal tran ...

2010

The Momentum Map In Poisson Geometry

Tudor Ratiu, Juan-Pablo Ortega

Every action on a Poisson manifold by Poisson diffeomorphisms lifts to a Hamiltonian action on its symplectic groupoid which has a canonically defined momentum map. We study various properties of this momentum map as well as its use in reduction. ...

2009

The geometric structure of complex fluids

Tudor Ratiu, François Gay-Balmaz

This paper develops the theory of affine Euler-Poincare and affine Lie-Poisson reductions and applies these processes to various examples of complex fluids, including Yang-Mills and Hall magnetohydrodynamics for fluids and superfluids, spin glasses, microf ...

Elsevier2009

Determination of local refractive index variations in thin films by heterodyne interferometric scanning near-field optical microscopy

Patrik Willi Hoffmann, Ali Dabirian, Yury Kuzminykh, Giacomo Benvenuti, Maria-Pilar Bernal

We report on a heterodyne interferometric scanning near-field optical microscope developed for characterizing, at the nanometric scale, refractive index variations in thin films. An optical lateral resolution of 80 nm (lambda/19) and a precision smaller th ...

American Institute of Physics2009

Reduced Lagrangian and Hamiltonian formulations of Euler-Yang-Mills fluids

Tudor Ratiu, François Gay-Balmaz

The Lagrangian and Hamiltonian structures for an ideal gauge-charged fluid are determined. Using a Kaluza-Klein point of view, the equations of motion are obtained by Lagrangian and Poisson reductions associated to the automorphism group of a principal bun ...

2008

Lectures on the Orbital Stability of Standing Waves and Application to the Nonlinear Schrodinger Equation

Charles Stuart

In the first part of these notes, we deal with first order Hamiltonian systems in the form Ju'(t) = del H(u(t)) where the phase space X may be in infinite dimensional so as to accommodate some partial differential equations. The Hamiltonian H is an element ...

Birkhäuser-Verlag, Springer2008

A path integral formalism of DNA looping probability

Ludovica Cotta-Ramusino

In this thesis we describe a path integral formalism to evaluate approximations to the probability density function for the location and orientation of one end of a continuum polymer chain at thermodynamic equilibrium with a heat bath. We concentrate on th ...

EPFL2008

Refractive multiple optical tweezers for parallel biochemical analysis in micro-fluidics

René Salathé, Fabrice Merenda, Horst Vogel, Johann Rohner, Jean-Marc Fournier

We present a multiple laser tweezers system based on refractive optics. The system produces an array of 100 optical traps thanks to a refractive microlens array, whose focal plane is imaged into the focal plane of a high-NA microscope objective. This refra ...

2007

Multiple scattering in optical coherence tomography. I. Investigation and modeling

Theo Lasser, Boris Clément Karamata, Marcel Leutenegger, Stéphane Bourquin, Markus Laubscher

We present a new model of optical coherence tomography (OCT) taking into account multiple scattering. A theoretical analysis and experimental investigation reveals that in OCT, despite multiple scattering, the field backscattered from the sample is general ...

2005

A scale-dependent Lagrangian dynamic model for large eddy simulation of complex turbulent flows

Marc Parlange, Charles Vivant Ignacio Meneveau

A scale-dependent dynamic subgrid model based on Lagrangian time averaging is proposed and tested in large eddy simulations sLESd of high-Reynolds number boundary layer flows over homogeneous and heterogeneous rough surfaces. The model is based on the Lagr ...

2005