Distortion-free tight confinement and step-like decay of fs pulses in free space

A method of formation of the tightly confined distortion-free fs pulses with the step-like decreasing of intensity under the finite-length propagation in free space is described. Such pulses are formed by the Fresnel source of a high refraction-index waveguide. The source reproduces in free space a propagation-invariant (distortion-free) pulse confined by… CONTINUE READING