Interference of a pair of symmetric Collett-Wolf beams.

We present a study of the interference of light produced by a pair of mutually correlated Gaussian Schell-model sources. The spatial distributions of the fields produced by these sources are symmetric with respect to a plane through their common center and differ by a phase factor exp(i phi). When phi = 0, the resulting radiation is a beam with an intensity distribution that displays a narrow bright line at its center. When the sources can be regarded as Collett-Wolf sources, the resulting bright line diverges much more slowly than the beam itself. When phi = pi the radiated beam has an intensity distribution with a narrow dark line at its center. The theoretical results are supported by experimental results obtained by use of a modified Michelson interferometer and suggest that the interference of a pair of correlated Collett-Wolf beams can be used to produce a pseudo-nondiffracting beam.