We study radiation-matter interaction in a system of ultracold atoms trapped in an optical lattice in a Mott insulator phase. We develop a fully general quantum model, and we perform calculations for a one-dimensional geometry at normal incidence. Both twoand three-level Λ atomic configurations are studied. The polariton dispersion and the reflectivity spectra are characterized in the different...

The current status of the software package PHASE for the propagation of coherent light pulses along a synchrotron radiation beamline is presented. PHASE is based on an asymptotic expansion of the Fresnel-Kirchhoff integral (stationary phase approximation) which is usually truncated at the 2 order. The limits of this approximation as well as possible extensions to higher orders are discussed. Th...

The origin and evolution of isotopes of the lightest elements H, He, Li, Be, B in the universe is a key problem in such fields as astrophysics of CR, Galactic evolution, non-thermal nucleosynthesis, and cosmological studies. One of the major sources of these species is spallation by CR nuclei in the interstellar medium. On the other hand, it is the B/C ratio in CR and Be abundance which are use...

An accurate numerical method is described for solving the Helmholtz equation for a general class of optical fibers. The method yields detailed information about the spatial and angular properties of the propagating beam as well as the modal propagation constants for the fiber. The method is applied to a practical graded-index fiber under the assumptions of both coherent and incoherent illuminat...

The theory of propagation of partially coherent light is well known, but performing numerical calculations still presents a difficulty because of the dimensionality of the problem. We propose using a recently introduced method based on the use of elementary functions [Wald et al. Proc. SPIE6040, 59621G (2005)] to reduce the integrals to two dimensions. We formalize the method, describe its inhe...

Light going through a participating medium like smoke can be scattered or absorbed by every point in the medium. To accurately render such a medium we must compute the radiance resulting at every point inside the medium because of these physical effects, which have been modeled by the radiative transfer equation. Computing the radiance at any point inside a participating medium amounts to numer...

Efficient light transport simulation in participating media is challenging in general, but especially if the medium is heterogeneous and exhibits significant multiple anisotropic scattering. We present a novel finite-element method that achieves interactive rendering speeds on modern GPUs without imposing any significant restrictions on the rendered participated medium. We achieve this by dynam...

We review the basic theory for the radiative transport equation governing light propagation in biological tissues. The Green’s function is the fundamental solution to the transport equation from which all other solutions can be computed. We compute the Green’s function as an analytical expansion in plane wave modes. We calculate these plane wave modes numerically using the discrete ordinate met...

We analyze electromagnetic field propagation through a random medium that consists of hyperbolic metamaterial domains separated by regions of normal "elliptic" space. This situation may occur in a problem as common as 9 μm light propagation through a pile of sand, or as exotic as electromagnetic field behavior in the early universe immediately after the electroweak phase transition. We demonstr...

We study, theoretically and experimentally, the evolution of optical waves with randomly-fluctuating phases in a spatially chirped nonlinear directional coupler. As the system crosses its linear resonance, we observe collective self-phase-locking (autoresonance) of all mutually-incoherent waves, each with its own pump, and simultaneous amplification until the pumps are exhausted. We show that t...