Experimental generation of a polychromatic partially coherent dark hollow beam

Abstract

We report experimental generation of a polychromatic partially coherent dark hollow beam (DHB) by coupling a polychromatic beam emitted from a light-emitting diode into a multimode fiber. The normalized spectrum of the generated partially coherent DHB is similar to that of the incident beam, while spectral shift exists. From the results of the double-slit interference experiment, we demonstrate that the multimode fiber increases the coherence of the output beam. Our method provides a convenient way for producing a polychromatic partially coherent dark hollow beam.