Pump induced Autler-Townes effect and A-T mixing in a four level atoms
  It is shown by theoretical simulation that tuning of the pump power can induce mixing and crossing of Autler-Townes(A-T)components of closely spaced transitions in atoms. Pump radiation also leads to small shifts of the central hole of A-T doublet. Off-resonance pumping gives an asymmetry in the A-T components and by controlling pump frequency detuning it is also possible to mix the A-T components. 
Dipankar Bhattacharyya, Biswajit Ray and Pradip N. Ghosh