Lineshapes of the Autler-Townes doublet induced by partially coherent pulsed laser fields

Lineshapes of the Autler-Townes doublet induced by longitudinally single mo de pulsed dye lasers were studied in Yb atoms. The doublet spectrum for the strongly driven transition 6s6p(1)S(0) --> 6s6p(3)P(1) of Yb atoms was obs erved using a weak probe laser which induced a transition to 6s(2)6p((7)/(2 ), (3)/(2))(2). The population of the state 6s(2)6p((7)/(2), (3)/(2))(2) co uld be monitored as a function of the probe laser detuning by using an addi tional time-delayed ionizing laser and detecting the ion yield. Numerical a nalysis was performed to explain the characteristics of the Autler-Townes d oublet by considering the statistical properties of dire laser fields in de nsity matrix equations. Our numerical predictions show good agreement with the experimental results for the peak-height asymmetry and the separations of the doublet. In addition. the phase correlation time of the dye laser fi eld could be determined from the numerical fit to the Autler-Townes spectra .