Autler-Townes triplet spectroscopy: An analytical approach

► The Autler-Townes triplet spectrum is analyzed analytically using state vector method. ► Two dark lines arise due to quantum interference which split the single Lorentzian peak into three spectral components. ► Each spectral component can be narrowed to up to 0.5 Γ. ► The analytical results show the generality over the Autler-Townes doublet spectrum.