Comment: Comment on “a new,versatile, three-pulse technique for the measurement of picosecond duration luminescent decay”

The method proposed by Mahr et al. is considered with respect to the influence of orientational relaxation on the measured signal.     

Observation of atomiclike electronic excitations in pure 3He and 4He clusters studied by fluorescence excitation spectroscopy

The structure of the electronically excited states of 3He and 4He clusters is investigated using fluorescence excitation spectroscopy. Distinct bands are observed energetically close to atomic 1s-ns, nd, np transitions and attributed to perturbed excited He atomiclike states with different principle and orbital quantum numbers. The line shifts and widths of the bands of 3He and 4He clusters of the same size are different and correlate with the average particle density inside the clusters calculated using the density functional method.     

Nonlinear and noise limitations in dispersion-managed soliton wavelength-division multiplexing transmissions with distributed Raman amplification

We the study limitations to error-free transmission distance as set by noise accumulation and nonlinear pulse interactions in dispersion-managed Nx40-Gbit/s transmission systems with either distributed backward Raman amplification or lumped erbium-doped fiber amplifiers. Significant performance improvement is achievable with Raman amplification.     

Nonlinear repolarization in optical fibers: polarization attraction with copropagating beams

We propose a type of lossless nonlinear polarizer, novel to our knowledge, a device that transforms any input state of polarization (SOP) of a signal beam into one and the same well-defined SOP toward the output, and perform this without any polarization-dependent losses. At the polarizer output end, the signal SOP appears to be locked to the input pump SOP. The polarizer is based on the nonlinear Kerr interaction of copropagating signal and pump beams in a telecom or randomly birefringent optical fiber.     

Multistep ionization of argon clusters in intense femtosecond extreme ultraviolet pulses

The interaction of intense extreme ultraviolet femtosecond laser pulses (lambda = 32.8 nm) from the FLASH free electron laser (FEL) with clusters has been investigated by means of photoelectron spectroscopy and modeled by Monte Carlo simulations. For laser intensities up to 5x10(13) W/cm(2), we find that the cluster ionization process is a sequence of direct electron emission events in a developing Coulomb field. A nanoplasma is formed only at the highest investigated power densities where ionization is frustrated due to the deep cluster potential. In contrast with earlier studies in the IR and vacuum ultraviolet spectral regime, we find no evidence for electron emission from plasma heating processes.