Integer and fractional electromagnetically induced Talbot effects in a ladder-type coherent atomic system.

Abstract

Both integer and fractional electromagnetically induced Talbot effects are experimentally investigated in a coherent rubidium 5S1/2 - 5P3/2 - 5D5/2 ladder-type system. By launching a probe laser into a periodically modulated lattice constructed by two crossed coupling fields with a small angle inside the rubidium vapor, a high-resolution diffraction pattern is obtained. The diffraction pattern is reproduced completely at detection positions of an integer multiple of twice the Talbot lengths. Meanwhile, the fractional Talbot effect, presented as complicated subimages at special positions, is also clearly observed. Furthermore, the theoretical simulations are conducted and agree well with the experimental results. These results pave the way for studying the control of light dynamics based on the periodically modulated medium.