Experimental study of discrete diffraction behavior in a coherent atomic system

Discrete diffraction behavior was experimentally studied in a coherent rubidium 5 S 1/2 − 5 P 3/2 − 5 D 5/2 cascade system. An optical lattice was established by the interference of two coupling lasers corresponding to 5 P 3/2 − 5 D 5/2 transition with a small angle. The distinct discrete diffraction patterns were observed in vapor when the probe laser corresponding to the 5 S 1/2 − 5 P 3 /2 transition propagated through the optical lattice. The optimized pertinent experimental parameters such as vapor temperature, two-photon detuning, coupling laser intensity and probe laser intensity are obtained. The experimental results are well analyzed utilizing the density-matrix theory. This system provides a new approach to investigate non-Hermitian physics and discrete solitons.