Department of Physics, Henan Normal University, Xinxiang 453007, China;
Department of Physics, Henan Normal University, Xinxiang 453007, China;
Department of Physics, Henan Normal University, Xinxiang 453007, China;
Department of Physics, Henan Normal University, Xinxiang 453007, China;
stimulated Raman adiabatic passage; coherent population transfer; delay time;