Ring dark solitary waves: experiment versus theory
  Theoretical and experimental results on optical ring dark solitary waves are presented, emphasizing the interplay between initial dark beam contrast, phase-shift magnitude, background-beam intensity and saturation of the nonlinearity are presented. The results are found to confirm qualitatively the existing analytical theory and are in agreement with the numerical simulations carried out. 
A. Dreischuh (1), D. Neshev (1), G. G. Paulus (2), F. Grasbon (2), H.   Walther (2,3) ((1) Sofia University, Department of Q...