We show that electromagnetically induced transparency suppresses nonlinear absorption of all orders in a multilevel atomic system and leads to selective, multiphoton excitation of resonantly coupled atomic states. Under appropriate conditions, higher-order nonlinear absorption becomes dominant and selective steady-state population inversion is created among the resonantly coupled states.
© 2004 Optical Society of America
Yifu Zhu, Joseph Saldana, Lingling Wen, and Ying Wu, "Steady-state population inversion by multiphoton electromagnetically induced transparency," J. Opt. Soc. Am. B 21, 806-810 (2004)