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 formalism for computing the signal-to-noise ratio (SNR) for laser radar is reviewed and applied to the tasks of target detection, direction finding, and phase-change estimation with squeezed light. The SNR for heterodyne detection of coherent light using a squeezed local oscillator is lower than that obtained using a coherent local oscillator. This is true for target detection, for phase es...

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...

We present a detailed analysis of the recently demonstrated technique to generate quasi-stationary pulses of light [M. Bajcsy et al., Nature (London) 426, 638 (2003)] based on electromagnetically induced transparency. We show that the use of counterpropagating control fields to retrieve a light pulse, previously stored in a collective atomic Raman excitation, leads to quasi-stationary light fie...

Dalian Coherent Light Source (DCLS) will use a 300MeV LINAC to produce fully coherent photon pulses in the wavelength range between 150-50nm by high gain harmonic generation free electron laser (FEL) scheme [1]. Beam quality requirements for the linear accelerator (linac) are critical, including not only the beam brightness, but also the stability and the reliability. In this paper, optimizatio...

We theoretically study the propagation of light in a disordered medium with nonlinear scatterers. We especially focus on interference effects between reversed multiple scattering paths, which lead to weak localization and coherent backscattering. We show that, in the presence of weakly nonlinear scattering, constructive interferences exist in general between three different scattering amplitude...

This paper describes the design and simulation of the electron beam collimation system in the Linac Coherent Light Source (LCLS). Dark current is expected from the gun and some of the accelerating cavities. Particle tracking of the expected dark current through the entire LCLS linac, from gun through FEL undulator, is used to estimate final particle extent in the undulator as well as expected b...

Recent two-dimensional electronic spectroscopy (2DES) experiments have reported evidence of coherent dynamics of electronic excitations in several light-harvesting antennae. However, 2DES uses ultrafast coherent laser pulses as an excitation source; therefore, there is a current debate on whether coherent excitation dynamics is present under natural sunlight - incoherent - illumination conditio...