$Diffraction solution superluminal$

$diffraction solution superluminal$ $diffraction solution superluminal$

DIFFRACTION SOLUTION SUPERLUMINAL FREE

DIFFRACTION SOLUTION SUPERLUMINAL FREE

Despite a number of experiments have been carried out on LW-s in acoustics, optics and microwave domain in free space and in dispersive media, ,, , the task has been satisfactorily solved only for simplest superluminal pulses вЂ“ the so-called X- or Bessel-X waves which can be generated from an ultrashort pulse by conical optics or annular slit and convergent lens. There are four families of LW-s distinguished by the shape of the support of the distribution of the plane waves in the momentum space and, correspondingly, by their superluminal, luminal or subluminal group velocity along the propagation axis. However, a real breakthrough here requires development of practical methods of generation of LW-s.Дue to the sophisticated non-separable temporal and spatial dependencies in the wavefunctions of LW-s, in order to generate them in reality the first task is to form a specific quasi-singular spatial distribution of the plane wave constituents of the wave field. Optical LW-s are prospective in many areas of application вЂ“ particle manipulation, trapping and acceleration, imaging, ultrafast spectroscopy, quantum optics and, especially, in nonlinear optics (see, e.g. Physical nature of the localized waves (LW) has been put to solid terms, ,, ,, , and number of different localized wave solutions to the scalar wave equation has been derived during the last quarter of century (see, and overviews, , ). Localized waves (also known as nondiffracting or undistorted progressive waves) are ultrawideband wave packets with both spatially and temporally highly localized instantaneous intensity distribution propagating without any spread or distortion in free space or in linear media.

$Diffraction solution superluminal$