Experimental Observation of Autler-Townes Splitting of Li2

Autler-Townes (A-T) splitting of the A1Σ+ustate of7Li2has been experimentally studied by pulsed optical-optical double resonance (OODR) spectroscopy. A stronger coupling field (the pump laser) excited an A1Σ+uv′, J′←X1Σ+gv″, J″transition and induced the A-Tsplitting of the A1Σ+uv′, J′and X1Σ+gv″, J″levels, while a detecting laser (the probe laser) detected theA-Tsplittingofthe intermediateA1Σ+uv′, J′level bythe further excitingtothe 41Σ+gstate and monitored the collision-induced violet fluorescence fromthe upper 41Σ+glevel. When the coupling laser frequency was tuned off resonance, the excitation signals displayed doublet splittingwhichwas proportional to the frequency detuning of the coupling laser under the experimental conditions. The dependence of relative intensities of the two lines on coupling and detecting laser intensities and buffer gas pressure was studied.