Nonlinear formation of hot image and double intense image for gain-typed wirelike scatterers

Abstract

The propagation of high-power laser beams modulated by gain-typed small-scale wirelike scatterer through a Kerr medium slab and free spaces is investigated. The formation of intense hot image is proved by analytical study and computer simulation. Moreover, the formation of double intense images is revealed by computer simulation. It is found that the double intense images are in a plane dozens of centimeters ahead the hot image plane and that the intensities of them are almost directly proportional to the intensity gain of the scatterer. The double intense image intensity and the hot image intensity have the similar variation tendency as the scatterer size increases, but the scatterer size difference between the maximums of them is dozens of micrometers. Moreover, interestingly, the distance between the two fringes for the double intense images has a relation with wavelength, similar to that for the distance between the fringes in single slot diffraction. Besides, the effect of object distance on the formation of double intense images is discussed. • The formations of hot image and double intense image are presented. • The double intense image plane is about 40 cm ahead the hot image plane. • The distance between the double intense image fringes increases as the wavelength increases. • The hot image and the double intense image peak at different scatterer size.